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1
Watson, Victoria Theresa, and Andrew Scott Medeiros. "The value of paleolimnology in reconstructing and managing ecosystem vulnerability: a systematic map." FACETS 6, no. 1 (January 1, 2021): 517–36. http://dx.doi.org/10.1139/facets-2020-0067.
Повний текст джерелаАнотація:
Vulnerability can measure an ecosystem’s susceptibility to change as a result of pressure or disturbance, but can be difficult to quantify. Reconstructions of past climate using paleolimnological methods can create a baseline to calibrate future projections of vulnerability, which can improve ecosystem management and conservation plans. Here, we conduct a systematic map to analyze the range and extent that paleolimnological published studies incorporated the concept of vulnerability. Additional themes of monitoring, management, conservation, restoration, or ecological integrity were also included. A total of 52 relevant unique articles were found, a majority of which were conducted in Europe or North America since 2011. Common themes identified included management and adaptation, with the latter heavily focussed on climate change or disturbance. From this, we can infer that the use of paleolimnology to discuss the concept of vulnerability is an emerging field. We argue that paleolimnology plays a valid role in the reconstruction of ecosystem vulnerability due to its capacity to broaden the scope of long-term monitoring, as well as its potential to help establish management and restoration plans. The use of paleolimnology in vulnerability analysis will provide a clearer lens of changes over time; therefore, it should be frequently implemented as a tool for vulnerability assessment.
2
Coibion, Olivier, and Yuriy Gorodnichenko. "Information Rigidity and the Expectations Formation Process: A Simple Framework and New Facts." American Economic Review 105, no. 8 (August 1, 2015): 2644–78. http://dx.doi.org/10.1257/aer.20110306.
Повний текст джерелаАнотація:
We propose a new approach to test the full-information rational expectations hypothesis which can identify whether rejections of the null arise from information rigidities. This approach quantifies the economic significance of departures from the null and the underlying degree of information rigidity. Applying this approach to US and international data of professional forecasters and other agents yields pervasive evidence consistent with the presence of information rigidities. These results therefore provide a set of stylized facts which can be used to calibrate imperfect information models. Finally, we document evidence of state-dependence in the expectations formation process. (JEL C53, D83, D84, E13, E31, E37)
3
Weigelt, Oliver, J. Charlotte Seidel, Lucy Erber, Johannes Wendsche, Yasemin Z. Varol, Gerald M. Weiher, Petra Gierer, Claudia Sciannimanica, Richard Janzen, and Christine J. Syrek. "Too Committed to Switch Off—Capturing and Organizing the Full Range of Work-Related Rumination from Detachment to Overcommitment." International Journal of Environmental Research and Public Health 20, no. 4 (February 17, 2023): 3573. http://dx.doi.org/10.3390/ijerph20043573.
Повний текст джерелаАнотація:
Work-related thoughts during off-job time have been studied extensively in occupational health psychology and related fields. We provide a focused review of the research on overcommitment—a component within the effort–reward imbalance model—and aim to connect this line of research to the most commonly studied aspects of work-related rumination. Drawing on this integrative review, we analyze survey data on ten facets of work-related rumination, namely (1) overcommitment, (2) psychological detachment, (3) affective rumination, (4) problem-solving pondering, (5) positive work reflection, (6) negative work reflection, (7) distraction, (8) cognitive irritation, (9) emotional irritation, and (10) inability to recover. First, we apply exploratory factor analysis to self-reported survey data from 357 employees to calibrate overcommitment items and to position overcommitment within the nomological net of work-related rumination constructs. Second, we leverage apply confirmatory factor analysis to self-reported survey data from 388 employees to provide a more specific test of uniqueness vs. overlap among these constructs. Third, we apply relative weight analysis to assess the unique criterion-related validity of each work-related rumination facet regarding (1) physical fatigue, (2) cognitive fatigue, (3) emotional fatigue, (4) burnout, (5) psychosomatic complaints, and (6) satisfaction with life. Our results suggest that several measures of work-related rumination (e.g., overcommitment and cognitive irritation) can be used interchangeably. Emotional irritation and affective rumination emerge as the strongest unique predictors of fatigue, burnout, psychosomatic complaints, and satisfaction with life. Our study is intended to assist researchers in making informed decisions on selecting scales for their research and paves the way for integrating research on the effort–reward imbalance and work-related rumination.
4
Hsieh, Tsung-Han, Ming-Xian Lin, Kuan-Ting Yeh, and Tsukasa Watanabe. "Calibration of a Rotary Encoder and a Polygon Using a Two-Autocollimator Method." Applied Sciences 13, no. 3 (January 31, 2023): 1865. http://dx.doi.org/10.3390/app13031865.
Повний текст джерелаАнотація:
In this work, we propose a two-autocollimator method in which all pitch angle deviations of a polygon and angle errors of a rotary encoder can be calibrated simultaneously. A polygon with any number of faces can be calibrated. Any face of the polygon has is a measurement cycle of one. Compared to a traditional method, cross-calibration calibrates a rotary encoder and a polygon. This method can simultaneously calibrate all pitch angle deviations of the polygon and angle errors of the rotary encoder. The measurement cycle depends on how many faces the polygon has. There are 24 measurement cycles for a 24-faced polygon. In the experiment, we use two autocollimators to calibrate a 24-faced polygon and the SelfA rotary encoder to conduct the proposed two-autocollimator method. According to the uncertainty evaluation, the expanded uncertainty is 0.46”. For a 95% confidence level, the coverage factor is 2.00. To verify all pitch angle deviations, the shift-angle method, based on cross-calibration, uses one autocollimator to measure the same polygon. The difference in pitch angle deviations is smaller than ± 0.28”. The maximum En-value is 0.58. The SelfA rotary encoder comprises 12 read heads and calibrates using self-calibration. The difference in angle errors is smaller than ± 0.27”. The maximum En-value is 0.59. The two En-values mean that the proposed two-autocollimator method is practical.
5
Tseng, Wen-Ta, Tzi-Ying Su, and John-Michael L. Nix. "Validating Translation Test Items via the Many-Facet Rasch Model." Psychological Reports 122, no. 2 (April 11, 2018): 748–72. http://dx.doi.org/10.1177/0033294118768664.
Повний текст джерелаАнотація:
This study applied the many-facet Rasch model to assess learners’ translation ability in an English as a foreign language context. Few attempts have been made in extant research to detect and calibrate rater severity in the domain of translation testing. To fill the research gap, this study documented the process of validating a test of Chinese-to-English sentence translation and modeled raters’ scoring propensity defined by harshness or leniency, expert/novice effects on severity, and concomitant effects on item difficulty. Two hundred twenty-five, third-year senior high school Taiwanese students and six educators from tertiary and secondary educational institutions served as participants. The students’ mean age was 17.80 years ( SD = 1.20, range 17–19). The exam consisted of 10 translation items adapted from two entrance exam tests. The results showed that this subjectively scored performance assessment exhibited robust unidimensionality, thus reliably measuring translation ability free from unmodeled disturbances. Furthermore, discrepancies in ratings between novice and expert raters were also identified and modeled by the many-facet Rasch model. The implications for applying the many-facet Rasch model in translation tests at the tertiary level were discussed.
6
Oliva, A., S. Akamatsu, and P. G. Schyns. "Chromatic Cues for Face Detection in Natural Scenes." Perception 26, no. 1_suppl (August 1997): 294. http://dx.doi.org/10.1068/v970316.
Повний текст джерелаАнотація:
One of the challenging problems of human and machine vision is the detection of objects against complex backgrounds. Our research addresses the question of how faces can be very quickly detected in naturalistic scenes on the basis of luminance and chromatic cues. Although luminance information varies with pose and illumination differences, chromatic information is by and large invariant under these transformations. Hence, chromatic information might be a very powerful cue for segmentation and detection. We compared faces of different pigmentation against background scenes of different colours. Specifically, colour histograms were computed in a perceptually uniform colour space (L*u*v*). We computed the Euclidian distances between the averages of the colour histograms of faces and scenes in L*u*v*. This metric was used to calibrate the contrast between face and scene colour in the experimental design. In a face detection task, subjects saw faces against scene backgrounds at a different distance in colour space. Each combination face - scene was presented for 120 ms (to prevent saccadic explorations), and the subject's task was to indicate whether or not a face was present. Controls involved face - scene pairs on an isoluminant background. Results revealed that luminance information did not affect detection on the basis of chromatic cues. Importantly, the metric of detectability in L*u*v* space between scene and faces predicted reaction times to detection.
7
Alshaibani, Abdullah, Sylvia Carrell, Li-Hsin Tseng, Jungmin Shin, and Alexander Quinn. "Privacy-Preserving Face Redaction Using Crowdsourcing." Proceedings of the AAAI Conference on Human Computation and Crowdsourcing 8 (October 1, 2020): 13–22. http://dx.doi.org/10.1609/hcomp.v8i1.7459.
Повний текст джерелаАнотація:
Redaction of private information from images is the kind of tedious, yet context-independent, task for which crowdsourcing is especially well suited. Despite tremendous progress, machine learning is not keeping pace with the needs of sensitive applications in which inadvertent disclosure could have real-world consequences. Human workers can detect faces that machines cannot; however, an open call to crowds would entail disclosure. We present IntoFocus, a method for engaging crowd workers to redact faces from images without disclosing the facial identities of people depicted. The method works iteratively, starting with a heavily filtered form of the image, and gradually reducing the strength of the filter, with a different set of workers reviewing the image at each step. IntoFocus exploits the gap between the filter level at which a face becomes unidentifiable and the level at which it becomes undetectable. To calibrate the algorithm, we performed a perceptual study of detection and identification of faces in images filtered with the median filter. We present the system design, the results of the perception study, and the results of a summative evaluation of the system
8
Sun, W., R. R. Baize, C. Lukashin, and Y. Hu. "Deriving polarization properties of desert-reflected solar spectra with PARASOL data." Atmospheric Chemistry and Physics 15, no. 13 (July 15, 2015): 7725–34. http://dx.doi.org/10.5194/acp-15-7725-2015.
Повний текст джерелаАнотація:
Abstract. One of the major objectives of the Climate Absolute Radiance and Refractivity Observatory (CLARREO) is to conduct highly accurate spectral observations to provide an on-orbit inter-calibration standard for relevant Earth-observing sensors with various channels. To calibrate an Earth-observing sensor's measurements with the highly accurate data from the CLARREO, errors in the measurements caused by the sensor's sensitivity to the polarization state of light must be corrected. For correction of the measurement errors due to the light's polarization, both the instrument's dependence on the incident polarization state and the on-orbit knowledge of the polarization state of light as a function of observed scene type, viewing geometry, and solar wavelength are required. In this study, an algorithm for deriving the spectral polarization state of solar light from the desert is reported. The desert/bare land surface is assumed to be composed of two types of areas: fine sand grains with diffuse reflection (Lambertian non-polarizer) and quartz-rich sand particles with facets of various orientations (specular-reflection polarizer). The Adding–Doubling Radiative Transfer Model (ADRTM) is applied to integrate the atmospheric absorption and scattering in the system. Empirical models are adopted in obtaining the diffuse spectral reflectance of sands and the optical depth of the dust aerosols over the desert. The ratio of non-polarizer area to polarizer area and the angular distribution of the facet orientations are determined by fitting the modeled polarization states of light to the measurements at three polarized channels (490, 670, and 865 nm) by the Polarization and Anisotropy of Reflectances for Atmospheric Science instrument coupled with Observations from a Lidar (PARASOL). Based on this physical model of the surface, the desert-reflected solar light's polarization state at any wavelength in the whole solar spectra can be calculated with the ADRTM.
9
Bonnefoy, Léa E., Jean-François Lestrade, Emmanuel Lellouch, Alice Le Gall, Cédric Leyrat, Nicolas Ponthieu, and Bilal Ladjelate. "Probing the subsurface of the two faces of Iapetus." EPJ Web of Conferences 228 (2020): 00006. http://dx.doi.org/10.1051/epjconf/202022800006.
Повний текст джерелаАнотація:
Saturn’s moon Iapetus, which is in synchronous rotation, is covered by an optically dark material mainly on its leading side, while its trailing side is significantly brighter. Because longer wavelengths probe deeper into the subsurface, observing both sides at a variety of wavelengths brings to light possible changes in thermal, compositional, and physical properties with depth. We have observed Iapetus’s leading and trailing hemispheres at 1.2 and 2.0 mm, using the NIKA2 camera mounted on the IRAM 30-m telescope, and compared our observations to others performed at mm to cm wavelengths. We calibrate our observations on Titan, which is simultaneously observed within the field of view. Due to the proximity of Saturn, it is sometimes difficult to separate Iapetus’s and Titan’s flux from that of Saturn, detected in the telescope’s side lobes. Preliminary results show that the trailing hemisphere brightness temperatures at the two wavelengths are equal within error bars, unlike the prediction made by Ries (2012)[1]. On the leading side, we report a steep spectral slope of increasing brightness temperature (by 10 K) from 1.2 to 2.0 mm, which may indicate rapidly varying emissivities within the top few centimeters of the surface. Comparison to a diffuse scattering model and a thermal model will be necessary to further constrain the thermophysical properties of the subsurface of Iapetus’s two faces.
10
Faberman, R. Jason, Andreas I. Mueller, Aysegül Sahin, and Giorgio Topa. "Job Search Behavior Among the Employed and Non‐Employed." Econometrica 90, no. 4 (2022): 1743–79. http://dx.doi.org/10.3982/ecta18582.
Повний текст джерелаАнотація:
We develop a unique survey that focuses on the job search behavior of individuals regardless of their labor force status and field it annually starting in 2013. We use our survey to study the relationship between search effort and outcomes for the employed and non‐employed. Three important facts stand out: (1) on‐the‐job search is pervasive, and is more intense at the lower rungs of the job ladder; (2) the employed are at least three times more effective than the unemployed in job search; and (3) the employed receive better job offers than the unemployed. We set up a general equilibrium model of on‐the‐job search with endogenous search effort, calibrate it to fit our new facts, and find that the search effort of the employed is highly elastic. We show that search effort substantially amplifies labor market responses to productivity shocks over the business cycle.
11
McQuoid, Alexander, and Loris Rubini. "MARKUP PREMIA OF EXPORTERS: BECAUSE OF EXPORTING, OR IN SPITE OF IT?" Macroeconomic Dynamics 23, no. 07 (March 12, 2018): 2959–3009. http://dx.doi.org/10.1017/s1365100517001018.
Повний текст джерелаАнотація:
We study the effect of exporting on markups building on two stylized facts: (1) exporters charge higher markups than nonexporters and (2) firms increase markups when they start to export. These facts suggest that exporting increases markups, but the causal relationship has not been studied directly. To do so, we modify Melitz and Ottaviano (2008) by adding decreasing returns technologies and demand and productivity shocks to account for sales correlations across markets. We calibrate and simulate a trade cost reduction. Old exporters increase markups on average, while new ones reduce them. Three mechanisms matter: (1) cost reductions are not fully passed on to prices, (2) firms expand, increasing marginal cost, and (3) foreign demand is more elastic than domestic demand. The first effect dominates along the intensive margin, while the others prevail along the extensive margin. Thus, exporters charge larger markups in spite of exporting, not because of it.
12
Hortaçsu, Ali, Gregor Matvos, Chaehee Shin, Chad Syverson, and Sriram Venkataraman. "Is an Automaker's Road to Bankruptcy Paved with Customers' Beliefs?" American Economic Review 101, no. 3 (May 1, 2011): 93–97. http://dx.doi.org/10.1257/aer.101.3.93.
Повний текст джерелаАнотація:
We explore the role the feedback loop between firms' financial health and consumers' demand for their products plays in the auto market. We construct a simple model of an automaker making pricing and debt service (continuation) decisions while recognizing that consumers are sensitive to whether it stays in business. We show that multiple equilibria can exist in such a model, and calibrate it to match stylized facts surrounding GM's recent bankruptcy. The results suggest that while the impact of financial distress on demand substantially reduced GM's profit, bank-run-like multiple equilibria do not appear likely in this market.
13
GUILLAUME, FLORENCE. "MULTIVARIATE OPTION PRICING MODELS WITH LÉVY AND SATO VG MARGINAL PROCESSES." International Journal of Theoretical and Applied Finance 21, no. 02 (March 2018): 1850007. http://dx.doi.org/10.1142/s0219024918500073.
Повний текст джерелаАнотація:
Pricing and hedging of financial instruments whose payoff depends on the joint realization of several underlyings (basket options, spread options, etc.) require multivariate models that are, at the same time, computationally tractable and flexible enough to accommodate the stylized facts of asset returns and of their dependence structure. Among the most popular models one finds models with VG marginals. The aim of this paper is to compare four multivariate models that are characterized by VG laws at unit time and to assess their performance by considering the flexibility they offer to calibrate the dependence structure for fixed marginals.
14
Santos, Carlos, Carina Almeida, Tiago Ramos, Felizardo Rocha, Rodrigo Oliveira, and Ramiro Neves. "Using a Hierarchical Approach to Calibrate SWAT and Predict the Semi-Arid Hydrologic Regime of Northeastern Brazil." Water 10, no. 9 (August 25, 2018): 1137. http://dx.doi.org/10.3390/w10091137.
Повний текст джерелаАнотація:
The Paraguaçu watershed in northeastern Brazil faces increasing water scarcity, with water resources unable to meet the increasing demand. Accurate assessment of water availability is thus essential for efficient planning and management of local resources. In this work, the potential of the SWAT model for predicting daily and monthly variability of the hydrologic regime of the Paraguaçu River was assessed. Model calibration/validation followed: (i) A hierarchical framework; (ii) the assessment of maximum, average and minimum streamflow based on paired t-test and linear regression analysis; and (iii) the definition of permanence curves for streamflow with a probability of occurrence of 90% (Q90) and 95% (Q95). The goodness-of-fit indicators revealed a “satisfactory” model performance (model efficiency ranged from 0.42 to 0.83) when predicting streamflow in monitored sub-basins using a unique set of parameters for wet and dry conditions. The flow duration curves also showed that the model underestimated higher flows resulting from extreme events but performed well for flows with exceedance probabilities of <90%. The regression analysis and paired t-test demonstrated that the SWAT model can be used for estimating maximum, average and minimum monthly streamflow in a region where information is insufficient to support water authorities in the decision-making process. The SWAT model can thus be considered adequate for simulating monthly streamflow in the Paraguaçu watershed.
15
Wei, Z., M. Y. He, and A. G. Evans. "Application of a Dynamic Constitutive Law to Multilayer Metallic Sandwich Panels Subject to Impulsive Loads." Journal of Applied Mechanics 74, no. 4 (April 19, 2006): 636–44. http://dx.doi.org/10.1115/1.2424471.
Повний текст джерелаАнотація:
The present paper describes an investigation that implements and assesses a dynamic continuum constitutive law for all-metallic sandwich panels. It also demonstrates its application to multilayer panels subject to water blast. Finite element calculations of unit cells are used to calibrate the model, especially the hardening curves at different strain rates. Once calibrated, the law is assessed by comparison with two sets of experiments. The dynamic response of panels impacted by Al foam projectiles at impulses comparable to those expected in water blast. The response of a multilayer core to an impulse caused by an explosion occurring in a cylindrical water column. The comparisons reveal that the overall deformation, average core strain, peak transmitted pressure, and velocities of the front and back faces are adequately predicted, inclusive of fluid/structure interactions. The inherent limitations of the approach are the underprediction of the plastic strains in the faces and incomplete assessment of stress oscillations beyond the peak. The former deficiency would pertain for any continuum representation for the core and would lead to problems in the prediction of face tearing. The latter may adversely affect the predictions of the impulse.
16
Sun, W., R. R. Baize, C. Lukashin, and Y. Hu. "Deriving polarization properties of desert-reflected solar spectra with PARASOL data." Atmospheric Chemistry and Physics Discussions 15, no. 6 (March 23, 2015): 8525–64. http://dx.doi.org/10.5194/acpd-15-8525-2015.
Повний текст джерелаАнотація:
Abstract. Highlights: 1. Spectral polarization state of reflected solar radiation is needed in correcting satellite data. 2. An algorithm for deriving spectral polarization state of solar light from desert is reported. 3. PARASOL data at 3 polarized channels are used in deriving polarization of whole spectra. 4. Desert-reflected solar ligh's polarization state at any wavelength can be obtained. One of the major objectives of the Climate Absolute Radiance and Refractivity Observatory (CLARREO) is to conduct highly accurate spectral observations to provide an on-orbit inter-calibration standard for relevant Earth observing sensors with various channels. To calibrate an Earth observing sensor's measurements with the highly accurate data from the CLARREO, errors in the measurements caused by the sensor's sensitivity to the polarization state of light must be corrected. For correction of the measurement errors due to the light's polarization, both the instrument's dependence to incidence's polarization status and the on-orbit knowledge of polarization state of light as function of observed scene type, viewing geometry, and solar wavelength, are required. In this study, an algorithm for deriving spectral polarization state of solar light from desert is reported. The desert/bare land surface is assumed to be composed of two types of areas: fine sand grains with diffuse reflection (Lambertian non-polarizer) and quartz-rich sand particles with facets of various orientations (specular-reflection polarizer). The adding-doubling radiative transfer model (ADRTM) is applied to integrate the atmospheric absorption and scattering in the system. Empirical models are adopted in obtaining the diffuse spectral reflectance of sands and the optical depth of the dust aerosols over the desert. The ratio of non-polarizer area to polarizer area and the angular distribution of the facet orientations are determined by fitting the modeled polarization states of light to the measurements at 3 polarized channels (490, 670, and 865 nm) by the Polarization and Anisotropy of Reflectances for Atmospheric Science instrument coupled with Observations from a Lidar (PARASOL). Based on this physical model of surface, desert-reflected solar light's polarization state at any wavelength in the whole solar spectra can be calculated with the ADRTM.
17
Ostermann, Frank O. "Linking Geosocial Sensing with the Socio-Demographic Fabric of Smart Cities." ISPRS International Journal of Geo-Information 10, no. 2 (January 27, 2021): 52. http://dx.doi.org/10.3390/ijgi10020052.
Повний текст джерелаАнотація:
Technological advances have enabled new sources of geoinformation, such as geosocial media, and have supported the propagation of the concept of smart cities. This paper argues that a city cannot be smart without citizens in the loop, and that a geosocial sensor might be one component to achieve that. First, we need to better understand which facets of urban life could be detected by a geosocial sensor, and how to calibrate it. This requires replicable studies that foster longitudinal and comparative research. Consequently, this paper examines the relationship between geosocial media content and socio-demographic census data for a global city, London, at two administrative levels. It aims for a transparent study design to encourage replication, using Term Frequency—Inverse Document Frequency of keywords, rule-based and word-embedding sentiment analysis, and local cluster analysis. The findings of limited links between geosocial media content and socio-demographic characteristics support earlier critiques on the utility of geosocial media for smart city planning purposes. The paper concludes that passive listening to publicly available geosocial media, in contrast to pro-active engagement with citizens, seems of limited use to understand and improve urban quality of life.
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Mete, Fiorella, David J. Corr, Michael P. Wilbur, and Ying Chen. "Bridge Response and Heavy Truck Classification Framework Based on a Two-Step Machine Learning Algorithm." Transportation Research Record: Journal of the Transportation Research Board 2676, no. 3 (December 2, 2021): 454–67. http://dx.doi.org/10.1177/03611981211052027.
Повний текст джерелаАнотація:
Collecting information on heavy trucks and monitoring the bridges which they regularly cross is important for many facets of infrastructure management. In this paper, a two-step algorithm is developed using bridge and truck data, by deploying sequentially unsupervised and supervised machine learning techniques. Longitudinal clustering of bridge data, concerning strain waveforms, is adopted to perform the first step of the algorithm, while image visual inspection and classification tree methods are applied to truck data concurrently in the second step. Both bridge and truck traffic must be monitored for a limited, yet significant, amount of time to calibrate the algorithm, which is then used to build a classification framework. The framework provides the same benefits of two data collection systems while only one needs to be operative. Depending on which monitoring system remains available, the framework enables the use of bridge data to identify the truck’s profile which generated it, or to estimate bridge response given the truck’s information. As a result, the present study aims to provide decision-makers with an effective way to monitor the whole bridge-traffic system, bridge managers to plan effective maintenance, and policymakers to develop ad hoc regulations.
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Cantillo, Victor, Miguel Jaller, and Jose Holguín-Veras. "The Colombian Strategic Freight Transport Model Based on Product Analysis." PROMET - Traffic&Transportation 26, no. 6 (December 30, 2014): 487–96. http://dx.doi.org/10.7307/ptt.v26i6.1460.
Повний текст джерелаАнотація:
Freight transport modelling at interregional scale is relevant for planning issues. However, freight modelling processes are complex because it is not easy to define the relevant variables in the analysis, and to obtain the required information on freight movements through the network. These facts raise the need to adapt the modelling framework to each context.This paper proposes a strategic national freight transport modelling framework developed as a variant of the traditional four-step modelling process with additional steps to estimate traffic flows from freight flows and to consider empty trips. The country of Colombia is used as the case study to implement and calibrate the proposed model. The data, data sources, and modelling methodologies used for each step are explained. In addition, data limitations and measures taken to complement the available data are discussed. From the implementation, the authors identify a set of advantages derived from the modelling approaches considered and suggestions for improvement.
20
Yan, Yuchun, and Hyeon-Jeong Suk. "Skin Balancing: Skin Color-Based Calibration for Portrait Images to Enhance the Affective Quality." Color and Imaging Conference 2019, no. 1 (October 21, 2019): 91–94. http://dx.doi.org/10.2352/issn.2169-2629.2019.27.17.
Повний текст джерелаАнотація:
Because our sensitivity to human skin color leads to a precise chromatic adjustment, skin color has been considered a calibration target to enhance the quality of images that contain human faces. In this paper, we investigated the perceived quality of portrait images depending on how the target skin color is defined: measured, memory, digital, or CCT skin color variations. A user study was conducted; 24 participants assessed the quality of white-balanced portraits on five criteria: reality, naturalness, appropriateness, preference, and emotional enhancement. The results showed that the calibration using measured skin color best served the aspects of reality and naturalness. With regard to appropriateness and preference, digital skin color obtained the highest score. Also, the memory skin color was appropriate to calibrate portraits with emotional enhancement. In addition, the other two CCT target colors enhanced the affective quality of portrait images, but the effect was quite marginal. In the foregoing, labelled Skin Balance, this study proposes a set of alternative targets for skin color, a simple but efficient way of reproducing portrait images with affective enhancement.
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Hamza, Karim, Kang-Ching Chu, Matthew Favetti, Peter Keene Benoliel, Vaishnavi Karanam, Kenneth P. Laberteaux, and Gil Tal. "Comparisons of Real-World Vehicle Energy Efficiency with Dynamometer-Based Ratings and Simulation Models." World Electric Vehicle Journal 12, no. 4 (September 25, 2021): 161. http://dx.doi.org/10.3390/wevj12040161.
Повний текст джерелаАнотація:
Software tools for fuel economy simulations play an important role during design stages of advanced powertrains. However, calibration of vehicle models versus real-world driving data faces challenges owing to inherent variations in vehicle energy efficiency across different driving conditions and different vehicle owners. This work utilizes datasets of vehicles equipped with OBD/GPS loggers to validate and calibrate FASTSim (software originally developed by NREL) vehicle models. The results show that window-sticker ratings (derived from dynamometer tests) can be reasonably accurate when averaged across many trips by different vehicle owners, but successfully calibrated FASTSim models can have better fidelity. The results in this paper are shown for nine vehicle models, including the following: three battery-electric vehicles (BEVs), four plug-in hybrid electric vehicles (PHEVs), one hybrid electric vehicle (HEV), and one conventional internal combustion engine (CICE) vehicle. The calibrated vehicle models are able to successfully predict the average trip energy intensity within ±3% for an aggregate of trips across multiple vehicle owners, as opposed to within ±10% via window-sticker ratings or baseline FASTSim.
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Smith, Michael G. "The March Events and Baku Commune of 1918." Russian History 41, no. 2 (May 18, 2014): 197–210. http://dx.doi.org/10.1163/18763316-04102006.
Повний текст джерелаАнотація:
This article investigates the March Events of 1918: city-wide fighting for control of Baku that involved the Bolshevik party, the Red Guards, and various Armenian and Azerbaijani militias. Besides many of these combatants, thousands of innocent Azerbaijanis and others (Caucasus peoples and Persians) perished in the hostilities. Focusing on the Events as an exercise of power and violence, I argue that the establishment of the Baku Commune (like the later formation of the multi-national Soviet Union) was indivisible from these circumstances of national and sectarian war. Drawing from Azerbaijani sources long-suppressed by the Communist regime, I recount some of the key contexts, mechanics, and legacies of the Events. As an elucidation of the facts, this study sets out to help historians calibrate their interpretations, better weigh the nature of Soviet power, and refine what we usually term “Armenian” or “Azerbaijani” aggression. These peoples were not preternaturally disposed to violence. Suffering was not the exclusive province of either community. Rather, political strategies have drawn them into cycles of violence and bonds of recrimination that have recurred sporadically into the present day.
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BOUZIANE, M’HAMED, and CHENG HSU. "A RULEBASE MODEL FOR DATA AND KNOWLEDGE INTEGRATION IN MULTIPLE SYSTEMS ENVIRONMENTS." International Journal on Artificial Intelligence Tools 02, no. 04 (December 1993): 485–509. http://dx.doi.org/10.1142/s0218213093000230.
Повний текст джерелаАнотація:
There are three aspects of integration that a computerized enterprise using multiple systems must address: (1) data integration (among, e.g., product design databases, shop floor control databases, and production planning databases), (2) knowledge integration (across various knowledge-based systems that share common enterprise facts, operating rules, or decision logic), and (3) data and knowledge integration (as as to, at least, calibrate databases with factbases and data models with knowledge models). A key issue in this integration problem is the global representation of knowledge (including data semantic constraints and application processing logic) in a form compatible with that of data resources. This paper develops a rulebase model to address this need. In particular, the model combines production rule and relation into a structure that allows (1) full factbase management, (2) inclusion of complete logic (both condition and action), and (3) efficient rulebase processing. It contributes directly to the problem of trigger management (or more generally, rule and event management) in both single-site and multiple-site data and knowledge systems. The model is implemented as a part of the Metadatabase system at Rensselaer.
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Lei, Ziang. "A Poisson Equation-Based Method for 3D Reconstruction of Animated Images." Advances in Mathematical Physics 2021 (November 27, 2021): 1–11. http://dx.doi.org/10.1155/2021/1547630.
Повний текст джерелаАнотація:
3D reconstruction techniques for animated images and animation techniques for faces are important research in computer graphics-related fields. Traditional 3D reconstruction techniques for animated images mainly rely on expensive 3D scanning equipment and a lot of time-consuming postprocessing manually and require the scanned animated subject to remain in a fixed pose for a considerable period. In recent years, the development of large-scale computing power of computer-related hardware, especially distributed computing, has made it possible to come up with a real-time and efficient solution. In this paper, we propose a 3D reconstruction method for multivisual animated images based on Poisson’s equation theory. The calibration theory is used to calibrate the multivisual animated images, obtain the internal and external parameters of the camera calibration module, extract the feature points from the animated images of each viewpoint by using the corner point detection operator, then match and correct the extracted feature points by using the least square median method, and complete the 3D reconstruction of the multivisual animated images. The experimental results show that the proposed method can obtain the 3D reconstruction results of multivisual animation images quickly and accurately and has certain real-time and reliability.
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Li, Gang. "Noisy information and stock market returns." Studies in Economics and Finance 33, no. 3 (August 1, 2016): 338–58. http://dx.doi.org/10.1108/sef-04-2015-0101.
Повний текст джерелаАнотація:
Purpose This paper aims to study whether noisy public information that investors receive about the expected aggregate dividend growth rate can help better understand the large average equity premium and stock return volatility in the US financial market. Design/methodology/approach This paper considers a dynamic asset pricing model with a representative agent, who cannot observe the expected growth rate of dividends and must learn its value by using noisy information. In addition, this paper presents a simple model for noisy information calibration. Findings With a coefficient of relative risk aversion below 10 and the time impatience parameter between 0 and 1, the calibrated model is able to yield an average risk-free interest rate, equity premium and stock return volatility that are close to the stylized facts in the US financial market. Originality/value First, this paper presents a different equilibrium model with a simple “catching up with the Joneses” preference and noisy information. Second, this paper develops a simple calibration procedure to calibrate the information process to study whether the calibrated model can help explain the large average equity premium and stock return volatility in the US financial market data.
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Remus, Robin, Andreas Lipphaus, Marc Neumann, and Beate Bender. "Calibration and validation of a novel hybrid model of the lumbosacral spine in ArtiSynth–The passive structures." PLOS ONE 16, no. 4 (April 26, 2021): e0250456. http://dx.doi.org/10.1371/journal.pone.0250456.
Повний текст джерелаАнотація:
In computational biomechanics, two separate types of models have been used predominantly to enhance the understanding of the mechanisms of action of the lumbosacral spine (LSS): Finite element (FE) and musculoskeletal multibody (MB) models. To combine advantages of both models, hybrid FE-MB models are an increasingly used alternative. The aim of this paper is to develop, calibrate, and validate a novel passive hybrid FE-MB open-access simulation model of a ligamentous LSS using ArtiSynth. Based on anatomical data from the Male Visible Human Project, the LSS model is constructed from the L1-S1 rigid vertebrae interconnected with hyperelastic fiber-reinforced FE intervertebral discs, ligaments, and facet joints. A mesh convergence study, sensitivity analyses, and systematic calibration were conducted with the hybrid functional spinal unit (FSU) L4/5. The predicted mechanical responses of the FSU L4/5, the lumbar spine (L1-L5), and the LSS were validated against literature data from in vivo and in vitro measurements and in silico models. Spinal mechanical responses considered when loaded with pure moments and combined loading modes were total and intervertebral range of motions, instantaneous axes and centers of rotation, facet joint contact forces, intradiscal pressures, disc bulges, and stiffnesses. Undesirable correlations with the FE mesh were minimized, the number of crisscrossed collagen fiber rings was reduced to five, and the individual influences of specific anatomical structures were adjusted to in vitro range of motions. Including intervertebral motion couplings for axial rotation and nonlinear stiffening under increasing axial compression, the predicted kinematic and structural mechanics responses were consistent with the comparative data. The results demonstrate that the hybrid simulation model is robust and efficient in reproducing valid mechanical responses to provide a starting point for upcoming optimizations and extensions, such as with active skeletal muscles.
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Jiang, Zhengbao, Jun Araki, Haibo Ding, and Graham Neubig. "How Can We Know When Language Models Know? On the Calibration of Language Models for Question Answering." Transactions of the Association for Computational Linguistics 9 (2021): 962–77. http://dx.doi.org/10.1162/tacl_a_00407.
Повний текст джерелаАнотація:
Abstract Recent works have shown that language models (LM) capture different types of knowledge regarding facts or common sense. However, because no model is perfect, they still fail to provide appropriate answers in many cases. In this paper, we ask the question, “How can we know when language models know, with confidence, the answer to a particular query?” We examine this question from the point of view of calibration, the property of a probabilistic model’s predicted probabilities actually being well correlated with the probabilities of correctness. We examine three strong generative models—T5, BART, and GPT-2—and study whether their probabilities on QA tasks are well calibrated, finding the answer is a relatively emphatic no. We then examine methods to calibrate such models to make their confidence scores correlate better with the likelihood of correctness through fine-tuning, post-hoc probability modification, or adjustment of the predicted outputs or inputs. Experiments on a diverse range of datasets demonstrate the effectiveness of our methods. We also perform analysis to study the strengths and limitations of these methods, shedding light on further improvements that may be made in methods for calibrating LMs. We have released the code at https://github.com/jzbjyb/lm-calibration.
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Peres, Caroline, Masoud Emam, Hamed Jafarzadeh, Marco Belcastro, and Brendan O’Flynn. "Development of a Low-Power Underwater NFC-Enabled Sensor Device for Seaweed Monitoring." Sensors 21, no. 14 (July 7, 2021): 4649. http://dx.doi.org/10.3390/s21144649.
Повний текст джерелаАнотація:
Aquaculture farming faces challenges to increase production while maintaining welfare of livestock, efficiently use of resources, and being environmentally sustainable. To help overcome these challenges, remote and real-time monitoring of the environmental and biological conditions of the aquaculture site is highly important. Multiple remote monitoring solutions for investigating the growth of seaweed are available, but no integrated solution that monitors different biotic and abiotic factors exists. A new integrated multi-sensing system would reduce the cost and time required to deploy the system and provide useful information on the dynamic forces affecting the plants and the associated biomass of the harvest. In this work, we present the development of a novel miniature low-power NFC-enabled data acquisition system to monitor seaweed growth parameters in an aquaculture context. It logs temperature, light intensity, depth, and motion, and these data can be transmitted or downloaded to enable informed decision making for the seaweed farmers. The device is fully customisable and designed to be attached to seaweed or associated mooring lines. The developed system was characterised in laboratory settings to validate and calibrate the embedded sensors. It performs comparably to commercial environmental sensors, enabling the use of the device to be deployed in commercial and research settings.
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Krishnan, Gokul, Sumit K. Mandal, Manvitha Pannala, Chaitali Chakrabarti, Jae-Sun Seo, Umit Y. Ogras, and Yu Cao. "SIAM: Chiplet-based Scalable In-Memory Acceleration with Mesh for Deep Neural Networks." ACM Transactions on Embedded Computing Systems 20, no. 5s (October 31, 2021): 1–24. http://dx.doi.org/10.1145/3476999.
Повний текст джерелаАнотація:
In-memory computing (IMC) on a monolithic chip for deep learning faces dramatic challenges on area, yield, and on-chip interconnection cost due to the ever-increasing model sizes. 2.5D integration or chiplet-based architectures interconnect multiple small chips (i.e., chiplets) to form a large computing system, presenting a feasible solution beyond a monolithic IMC architecture to accelerate large deep learning models. This paper presents a new benchmarking simulator, SIAM, to evaluate the performance of chiplet-based IMC architectures and explore the potential of such a paradigm shift in IMC architecture design. SIAM integrates device, circuit, architecture, network-on-chip (NoC), network-on-package (NoP), and DRAM access models to realize an end-to-end system. SIAM is scalable in its support of a wide range of deep neural networks (DNNs), customizable to various network structures and configurations, and capable of efficient design space exploration. We demonstrate the flexibility, scalability, and simulation speed of SIAM by benchmarking different state-of-the-art DNNs with CIFAR-10, CIFAR-100, and ImageNet datasets. We further calibrate the simulation results with a published silicon result, SIMBA. The chiplet-based IMC architecture obtained through SIAM shows 130 and 72 improvement in energy-efficiency for ResNet-50 on the ImageNet dataset compared to Nvidia V100 and T4 GPUs.
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Miles, Katie E., Evan S. Miles, Bryn Hubbard, Duncan J. Quincey, Ann V. Rowan, and Mark Pallett. "Instruments and methods: hot-water borehole drilling at a high-elevation debris-covered glacier." Journal of Glaciology 65, no. 253 (September 6, 2019): 822–32. http://dx.doi.org/10.1017/jog.2019.49.
Повний текст джерелаАнотація:
AbstractWhile hot-water drilling is a well-established technique used to access the subsurface of ice masses, drilling into high-elevation (≳ 4000 m a.s.l.) debris-covered glaciers faces specific challenges. First, restricted transport capacity limits individual equipment items to a volume and mass that can be slung by small helicopters. Second, low atmospheric oxygen and pressure reduces the effectiveness of combustion, limiting a system's ability to pump and heat water. Third, thick supraglacial debris, which is both highly uneven and unstable, inhibits direct access to the ice surface, hinders the manoeuvring of equipment and limits secure sites for equipment placement. Fourth, englacial debris can slow the drilling rate such that continued drilling becomes impracticable and/or boreholes deviate substantially from vertical. Because of these challenges, field-based englacial and subglacial data required to calibrate numerical models of high-elevation debris-covered glaciers are scarce or absent. Here, we summarise our experiences of hot-water drilling over two field seasons (2017–2018) at the debris-covered Khumbu Glacier, Nepal, where we melted 27 boreholes up to 192 m length, at elevations between 4900 and 5200 m a.s.l. We describe the drilling equipment and operation, evaluate the effectiveness of our approach and suggest equipment and methodological adaptations for future use.
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Chen, Keyao, Guizhi Wang, Lingyan Wu, Jibo Chen, Shuai Yuan, Qi Liu, and Xiaodong Liu. "PM2.5 Pollution: Health and Economic Effect Assessment Based on a Recursive Dynamic Computable General Equilibrium Model." International Journal of Environmental Research and Public Health 16, no. 24 (December 13, 2019): 5102. http://dx.doi.org/10.3390/ijerph16245102.
Повний текст джерелаАнотація:
At present particulate matter (PM2.5) pollution represents a serious threat to the public health and the national economic system in China. This paper optimizes the whitening coefficient in a grey Markov model by a genetic algorithm, predicts the concentration of fine particulate matter (PM2.5), and then quantifies the health effects of PM2.5 pollution by utilizing the predicted concentration, computable general equilibrium (CGE), and a carefully designed exposure–response model. Further, the authors establish a social accounting matrix (SAM), calibrate the parameter values in the CGE model, and construct a recursive dynamic CGE model under closed economy conditions to assess the long-term economic losses incurred by PM2.5 pollution. Subsequently, an empirical analysis was conducted for the Beijing area: Despite the reduced concentration trend, PM2.5 pollution continued to cause serious damage to human health and the economic system from 2013 to 2020, as illustrated by various facts, including: (1) the estimated premature deaths and individuals suffering haze pollution-related diseases are 156,588 (95% confidence intervals (CI): 43,335–248,914)) and six million, respectively; and (2) the accumulated labor loss and the medical expenditure negatively impact the regional gross domestic product, with an estimated loss of 3062.63 (95% CI: 1,168.77–4671.13) million RMB. These findings can provide useful information for governmental agencies to formulate relevant environmental policies and for communities to promote prevention and rescue strategies.
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Armitage, Kristy L., Adam Bulley, and Jonathan Redshaw. "Developmental origins of cognitive offloading." Proceedings of the Royal Society B: Biological Sciences 287, no. 1928 (June 10, 2020): 20192927. http://dx.doi.org/10.1098/rspb.2019.2927.
Повний текст джерелаАнотація:
Many animals manipulate their environments in ways that appear to augment cognitive processing. Adult humans show remarkable flexibility in this domain, typically relying on internal cognitive processing when adequate but turning to external support in situations of high internal demand. We use calendars, calculators, navigational aids and other external means to compensate for our natural cognitive shortcomings and achieve otherwise unattainable feats of intelligence. As yet, however, the developmental origins of this fundamental capacity for cognitive offloading remain largely unknown. In two studies, children aged 4–11 years ( n = 258) were given an opportunity to manually rotate a turntable to eliminate the internal demands of mental rotation––to solve the problem in the world rather than in their heads. In study 1, even the youngest children showed a linear relationship between mental rotation demand and likelihood of using the external strategy, paralleling the classic relationship between angle of mental rotation and reaction time. In study 2, children were introduced to a version of the task where manually rotating inverted stimuli was sometimes beneficial to performance and other times redundant. With increasing age, children were significantly more likely to manually rotate the turntable only when it would benefit them. These results show how humans gradually calibrate their cognitive offloading strategies throughout childhood and thereby uncover the developmental origins of this central facet of intelligence.
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Sieber, John R. "How to use and how not to use certified reference materials in industrial chemical metrology laboratories." Powder Diffraction 35, no. 2 (April 15, 2020): 104–11. http://dx.doi.org/10.1017/s0885715620000202.
Повний текст джерелаАнотація:
As a producer of certified reference materials (CRMs), NIST faces high demand for Standard Reference Materials (SRMs). The demand is exacerbated by widespread misuse of CRMs. When should one use CRMs? When should one not use CRMs? Must labs always use NIST SRMs? How can labs demonstrate analytical capabilities for their accreditation scopes? Why so many questions? Standards developers, laboratory accreditors, and laboratory staff must be able to understand these topics with respect to quality systems in compliance with ISO/IEC 17025. They must calibrate and validate test methods and document traceability to the International System of Units (SI). Many people working in laboratory accreditation and under the umbrella of a quality system do not fully understand what these things are, let alone the language of chemical metrology. On average, they have little training in analytical chemistry, elemental analysis, and reference material development. It is hoped this paper will impress upon the reader the need for understanding how CRMs can be best used in the laboratory. This paper provides a brief background on the above problems and then looks at some of the support and reference information provided by NIST to metals and mining industries labs, commercial CRM producers, and accrediting bodies. The concepts and guidance apply broadly to chemical metrology and fundamental analytical chemistry. The paper includes examples (some from X-ray fluorescence spectrometry) to illustrate concepts.
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Sainov, Mikhail P., and Vladislav B. Soroka. "Enhancement of a seepage control facility of an earth-filled dam that has a concrete face and a cutoff wall." Stroitel'stvo: nauka i obrazovanie [Construction: Science and Education] 12, no. 1 (March 30, 2022): 17–37. http://dx.doi.org/10.22227/2305-5502.2022.1.2.
Повний текст джерелаАнотація:
Introduction. When a rockfill dam with a concrete face is constructed on the earth foundation, its seepage control facility is complemented by a cutoff wall and an apron. Together they represent a complicated integrated seepage control facility. The performance of an integrated seepage control facility gains relevance, which is proven by the experience in the operation of a number of dams, whose concrete faces and cutoff walls may be in the adverse stress state. Towards this end, the authors studied the stress-strain state (SSS) of an integrated seepage control facility. Materials and methods. The study was conducted at the Miaojiaba rockfill dam that has an integrated seepage control facility. This dam is 111 m high and 348 m long; its riverbed is about 45 m thick. Numerical modeling using the finite element method was performed to study the spatial SSS of this dam. Measurements of the dam displacements were taken to calibrate the finite element model. Results. The SSS of the dam was analyzed to develop two alternative structural designs of an integrated seepage control facility. As for the first design option, each element (the face, the cutoff wall, the apron) is made of concrete. The analysis of this option has shown that compressive and tensile stresses, arising in the cutoff wall, exceed the strength of concrete. Besides, the cutoff wall gets separated from the foundation. Within the framework of the second option, the cutoff wall is made of clay-cement concrete. According to the results of the analysis, this design option ensures the sufficient strength of all components of a seepage control facility. Conclusions. To ensure the strength of a seepage control facility that has a concrete face, a cutoff wall and a connecting apron, the cutoff wall and the apron should be made of less rigid materials.
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Driessen, T. L. A., and M. van Ledden. "The large-scale impact of climate change to Mississippi flood hazard in New Orleans." Drinking Water Engineering and Science 6, no. 2 (July 12, 2013): 81–87. http://dx.doi.org/10.5194/dwes-6-81-2013.
Повний текст джерелаАнотація:
Abstract. The objective of this paper was to describe the impact of climate change on the Mississippi River flood hazard in the New Orleans area. This city has a unique flood risk management challenge, heavily influenced by climate change, since it faces flood hazards from multiple geographical locations (e.g. Lake Pontchartrain and Mississippi River) and multiple sources (hurricane, river, rainfall). Also the low elevation and significant subsidence rate of the Greater New Orleans area poses a high risk and challenges the water management of this urban area. Its vulnerability to flooding became dramatically apparent during Hurricane Katrina in 2005 with huge economic losses and a large number of casualties. A SOBEK Rural 1DFLOW model was set up to simulate the general hydrodynamics. This model included the two important spillways that are operated during high flow conditions. A weighted multi-criteria calibration procedure was performed to calibrate the model for high flows. Validation for floods in 2011 indicated a reasonable performance for high flows and clearly demonstrated the influence of the spillways. 32 different scenarios were defined which included the relatively large sea level rise and the changing discharge regime that is expected due to climate change. The impact of these scenarios on the water levels near New Orleans were analysed by the hydrodynamic model. Results showed that during high flows New Orleans will not be affected by varying discharge regimes, since the presence of the spillways ensures a constant discharge through the city. In contrary, sea level rise is expected to push water levels upwards. The effect of sea level rise will be noticeable even more than 470 km upstream. Climate change impacts necessitate a more frequent use of the spillways and opening strategies that are based on stages.
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Chavez, Jose C., Juan Enciso, Manyowa N. Meki, Jaehak Jeong, and Vijay P. Singh. "Simulation of Energy Sorghum under Limited Irrigation Levels Using the EPIC Model." Transactions of the ASABE 61, no. 1 (2018): 121–31. http://dx.doi.org/10.13031/trans.12470.
Повний текст джерелаАнотація:
Abstract. Energy sorghum is one of the most attractive alternatives for producing energy in many regions of the world because of the high biomass productivity obtained in a short period. However, it faces many challenges, particularly where water resources are limited. Crop simulation models are suitable decision support tools for the assessment of crop water use and biomass production under different spatial and climatic conditions. Calibration of simulation models to local conditions is a necessary procedure to improve model reliability. The objective of this study was to calibrate and evaluate the Environmental Policy Integrated Climate (EPIC) model for the production of energy sorghum under different irrigation levels. The model was then used to simulate crop biomass productivity and crop water use to identify appropriate irrigation strategies. This study was conducted at the Texas A&M AgriLife Research Center in Weslaco, Texas. Simulations were performed to determine the total dry biomass, crop water use, the relationship between crop productivity and crop evapotranspiration (ETc), and water use efficiency (WUE). Simulated ETc agreed well with estimates from a weather station, except for a few simulation events. The statistical parameters derived from measured versus simulated dry biomass in the calibrated model, which indicated that the model performed well, were R2 = 0.99 and PBIAS = -5.35%. The calibrated model showed great potential for simulating the total dry biomass. At full irrigation, the difference between measured and simulated total dry biomass was 4.3% in 2013 and 3.0% in 2015. This study showed that energy sorghum requires approximately 600 mm of water to obtain 23 Mg ha-1 of total dry biomass. It also demonstrated that the EPIC model could be used for assessment of crop water use and total biomass under limited irrigation levels, especially in semi-arid regions. Keywords: Crop model, Dry biomass, Energy sorghum, EPIC model, Irrigation, Model calibration, Water use efficiency.
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Driessen, T. L. A., and M. van Ledden. "The large-scale impact of climate change to Mississippi flood hazard in New Orleans." Drinking Water Engineering and Science Discussions 5, no. 1 (July 5, 2012): 333–49. http://dx.doi.org/10.5194/dwesd-5-333-2012.
Повний текст джерелаАнотація:
Abstract. The objective of this paper is to describe the impact of climate change on the Mississippi River flood hazard in the New Orleans area. This city has a unique flood risk management challenge, heavily influenced by climate change, since it faces flood hazards from multiple geographical locations (e.g. Lake Pontchartrain and Mississippi River) and multiple sources (hurricane, river, rainfall). Also the low elevation and significant subsidence rate of the Greater New Orleans area poses a high risk and challenges the water management of this urban area. Its vulnerability to flooding became dramatically apparent during Hurricane Katrina in 2005 with huge economic losses and a large number of casualties. A SOBEK Rural 1DFLOW model was set up to simulate the general hydrodynamics. This improved model includes two important spillways that are operated during high flow conditions. Subsequently, a weighted multi-criteria calibration procedure was performed to calibrate the model for high flows. Validation for floods in 2011 indicates a very reasonable performance for high flows and clearly demonstrates the necessity of the spillways. 32 different scenarios are defined which includes the relatively large sea level rise and the changing discharge regime that is expected due to climate change. The impact of these scenarios is analysed by the hydrodynamic model. Results show that during high flows New Orleans will not be affected by varying discharge regimes, since the presence of the spillways ensures a constant discharge through the city. In contrary, sea level rise is expected to push water levels upwards. The effect of sea level rise will be noticeable even more than 470 km upstream. Climate change impacts necessitate a more frequent use of the spillways and opening strategies that are based on stages. Potential alternatives on how to cope with the flood hazard of this river in the long term, such as river widening and large-scale redistribution of the flow through diversions, are proposed.
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Ye, Qiming, Yuxiang Feng, Eduardo Candela, Jose Escribano Macias, Marc Stettler, and Panagiotis Angeloudis. "Spatial-Temporal Flows-Adaptive Street Layout Control Using Reinforcement Learning." Sustainability 14, no. 1 (December 23, 2021): 107. http://dx.doi.org/10.3390/su14010107.
Повний текст джерелаАнотація:
Complete streets scheme makes seminal contributions to securing the basic public right-of-way (ROW), improving road safety, and maintaining high traffic efficiency for all modes of commute. However, such a popular street design paradigm also faces endogenous pressures like the appeal to a more balanced ROW for non-vehicular users. In addition, the deployment of Autonomous Vehicle (AV) mobility is likely to challenge the conventional use of the street space as well as this scheme. Previous studies have invented automated control techniques for specific road management issues, such as traffic light control and lane management. Whereas models and algorithms that dynamically calibrate the ROW of road space corresponding to travel demands and place-making requirements still represent a research gap. This study proposes a novel optimal control method that decides the ROW of road space assigned to driveways and sidewalks in real-time. To solve this optimal control task, a reinforcement learning method is introduced that employs a microscopic traffic simulator, namely SUMO, as its environment. The model was trained for 150 episodes using a four-legged intersection and joint AVs-pedestrian travel demands of a day. Results evidenced the effectiveness of the model in both symmetric and asymmetric road settings. After being trained by 150 episodes, our proposed model significantly increased its comprehensive reward of both pedestrians and vehicular traffic efficiency and sidewalk ratio by 10.39%. Decisions on the balanced ROW are optimised as 90.16% of the edges decrease the driveways supply and raise sidewalk shares by approximately 9%. Moreover, during 18.22% of the tested time slots, a lane-width equivalent space is shifted from driveways to sidewalks, minimising the travel costs for both an AV fleet and pedestrians. Our study primarily contributes to the modelling architecture and algorithms concerning centralised and real-time ROW management. Prospective applications out of this method are likely to facilitate AV mobility-oriented road management and pedestrian-friendly street space design in the near future.
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Jones, Russell, and John Llewellyn. "Maintaining Stable Macroeconomic Conditions." National Institute Economic Review 250 (November 2019): R7—R14. http://dx.doi.org/10.1177/002795011925000111.
Повний текст джерелаАнотація:
Executive SummaryThe UK economy faces more than usually uncertain times. Outside the European Union, and in an increasingly challenging global environment characterised by ageing populations, climate change, populism, protectionism, and more, the country needs to chart a new course. This may well require policymakers to consider unconventional approaches to monetary and fiscal policy and, at the very least argues for important modifications of the current policy regime, including the autonomous mandate of the Bank of England.At some point, there will be a major slowdown in economic activity. Yet the Bank of England has very little leeway to respond by cutting interest rates, and it has already adopted an armoury of unorthodox tools that may be decreasing in effectiveness. More radical monetary approaches would be likely to be politically controversial; and are not without risks. In these circumstances it would be a mistake to rely solely, or even largely, on monetary policy to maintain demand. It would be better to conduct monetary and fiscal policy in tandem, and for discretionary fiscal policy to be required to play a much more active role in demand management than hitherto. This would, for example, imply major extension of the automatic stabilisers and efforts better to calibrate discretionary initiatives with the business cycle.But given the long-term pressures on the public finances, more fundamental changes in the structure of spending and taxation are needed, along with a redrawing of fiscal rules and targets, under independent budgetary oversight. The current, historically low, share in GDP of public spending is itself unsustainable in light of the demand for services of an ageing population; plans should be made to raise it closer to the European average. In the most extreme circumstances it might become necessary to waive the fiscal rules entirely and for the Bank of England directly to underwrite fiscal stimulus in order to sustain aggregate demand. It would be wise for the authorities to consider the options in detail now, while the environment is still relatively stable.
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Heesen, V., E. Buie II, C. J. Huff, L. A. Perez, J. G. Woolsey, D. A. Rafferty, A. Basu, et al. "Calibrating the relation of low-frequency radio continuum to star formation rate at 1 kpc scale with LOFAR." Astronomy & Astrophysics 622 (February 2019): A8. http://dx.doi.org/10.1051/0004-6361/201833905.
Повний текст джерелаАнотація:
Context. Radio continuum (RC) emission in galaxies allows us to measure star formation rates (SFRs) unaffected by extinction due to dust, of which the low-frequency part is uncontaminated from thermal (free–free) emission. Aims. We calibrate the conversion from the spatially resolved 140 MHz RC emission to the SFR surface density (ΣSFR) at 1 kpc scale. Radio spectral indices give us, by means of spectral ageing, a handle on the transport of cosmic rays using the electrons as a proxy for GeV nuclei. Methods. We used recent observations of three galaxies (NGC 3184, 4736, and 5055) from the LOFAR Two-metre Sky Survey (LoTSS), and archival LOw-Frequency ARray (LOFAR) data of NGC 5194. Maps were created with the facet calibration technique and converted to radio ΣSFR maps using the Condon relation. We compared these maps with hybrid ΣSFR maps from a combination of GALEX far-ultraviolet and Spitzer 24 μm data using plots tracing the relation at the highest angular resolution allowed by our data at 1.2 × 1.2 kpc2 resolution. Results. The RC emission is smoothed with respect to the hybrid ΣSFR owing to the transport of cosmic-ray electrons (CREs) away from star formation sites. This results in a sublinear relation (ΣSFR)RC ∝ [(ΣSFR)hyb]a, where a = 0.59 ± 0.13 (140 MHz) and a = 0.75 ± 0.10 (1365 MHz). Both relations have a scatter of σ = 0.3 dex. If we restrict ourselves to areas of young CREs (α > −0.65; Iν ∝ να), the relation becomes almost linear at both frequencies with a ≈ 0.9 and a reduced scatter of σ = 0.2 dex. We then simulate the effect of CRE transport by convolving the hybrid ΣSFR maps with a Gaussian kernel until the RC–SFR relation is linearised; CRE transport lengths are l = 1–5 kpc. Solving the CRE diffusion equation, assuming dominance of the synchrotron and inverse-Compton losses, we find diffusion coefficients of D = (0.13–1.5) × 1028 cm2 s−1 at 1 GeV. Conclusions. A RC–SFR relation at 1.4 GHz can be exploited to measure SFRs at redshift z ≈ 10 using 140 MHz observations.
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Brocardo, Graciela Aparecida, Carla Rosa Teixeira de Godoy, Débora Levy, Lis Vilela de Almeida, Gracia Martinez, Dalton Chamone, and Juliana Pereira. "A New Accurate and Reproducible Method to Assess Telomere Length by Flow-FISH." Blood 114, no. 22 (November 20, 2009): 4719. http://dx.doi.org/10.1182/blood.v114.22.4719.4719.
Повний текст джерелаАнотація:
Abstract Abstract 4719 Background Telomeres have been related to many diseases including cancer, medullar insufficiency and to understand aging. To measure the average length of telomere repeats have been described at least three methods as Southern blot and quantitative fluorescence in situ hybridization using either digital fluorescence microscopy (Q-FISH) or flow cytometry (Flow-FISH). After two independents groups (Hultdin et al., 1998 and Rufer et al., 1999) have described different protocols using Flow-FISH to measure telomere lengths, the Southern blot and Q-FISH methods have been less used. However, when we were performed Hultdin et al., 1998 or Rufer et al., 1999 protocols were found some facts that could cause mistakes in the final results. Afterward, many steps of these protocols were explored to become the Flow-FISH results more accurate and reproducible. In our laboratory we developed a unlike protocol to assess the average length of telomere repeats by Flow-FISH taking advantage of the both Hultdin et al., 1998 and Rufer et al., 1999 techniques that was named Modified Hultdin and Rufer protocol. Methods We compare the telomere length repeats measure by three different methods of Flow-FISH with or lacking standard beads for calibrate fluorescence intensity, control cell line 1301 and compensation by DNA index of G0/G1 cells. Results We demonstrated a linear relationship between the average length of telomere repeats by Hultdin et al., 1998 protocol and Modified Hultdin and Rufer protocol but showing that standard beads to quantify the fluorescence intensity was important to determine telomere length by Flow-FISH. However, the coefficient correlation (r) between the Rufer et al., 1999 protocol with Hultdin et al., 1998 and Modified Hultdin and Rufer protocols in our laboratory was poor, justifying of the internal control cell and compensation of the telomere length by DNA index of G0/G1 of unknown cells use. Conclusions We conclude that use of appropriate internal control cells with knowledge telomere length and DNA index is essential to improve accuracy and reproducibility of the telomere length measurement by Flow-FISH. Indeed the standard beads for fluorescence intensity quantification can allow intercenters comparison of the results. Disclosures: No relevant conflicts of interest to declare.
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Gamana Pratama, A. A. Gede Trisna. "Kajian Fasad Bangunan terhadap Visual Connection di Koridor Jalan Teuku Umar, Denpasar." RUANG-SPACE, Jurnal Lingkungan Binaan (Space : Journal of the Built Environment) 6, no. 1 (April 30, 2019): 49. http://dx.doi.org/10.24843/jrs.2019.v06.i01.p05.
Повний текст джерелаАнотація:
The development and growth of Denpasar City is accompanied by the development of diverse architecture. Mainly at Teuku Umar streetas one of the commercial centers there. It will affect the image of a city if the building façade doesn’t directed according to how the government wants based on regional Regulation Number 27 of 2011 about Denpasar city layout project. This research uses descriptive qualitative research with rationalistic approach based on the facts at the field, with primary data observations and direct documentation of building facade. The results of this research indicate visual connection which formed in this corridor is dominated by commercial buildings, so it contributes the modern building architectural image which is dominated.This kind of thing is still outlyingfrom what was expected from the look of Denpasar city. Whereas Denpasar should be a cultural insightful city although Teuku Umar street is one of the commercial and services center in Denpasar city. Denpasar government who take the responsibility of the wisdom is expected to make the reference of using building façade more specific based on the function of the building itself and not to generalize them. So as the function of commercial calibrate the look of the building that can attract the interest of customers and also can appropriate to how Denpasar city wants the city look like.
Keywords: building facade, visual connection, Teuku Umar street corridor Denpasar (Times New Roman 10t,
Blank, Times New Roman 12pt, Single-before 0-after 6)
Abstrak (Times New Roman 12pt, Bold, Multiple at 1.15-before 0-after 6)
Perkembangan dan pertumbuhan Kota Denpasar diiringi dengan perkembangan arsitektur yang beragam.Terutama di koridor Jalan Teuku Umar sebagai salah satu pusat komersial di Kota Denpasar. Hal tersebut mempengaruhi image sebuah koridor kota melalui tampilan fasad bangunan yang ada, tidak diarahkan sesuai wajah kota yang dinginkan pemerintah berdasarkan Peraturan Daerah No 27 Tahun 2011 tentang Rencana Tata Ruang Wilayah Kota Denpasar. Penelitian ini menggunakan penelitian kualitatif deskriptif dengan pendekatan rasionalistik berdasarkan kenyataan dilapangan, dengan data primer diperoleh dari hasil observasi, dokumentasi langsung berupa image fasad bangunan. Hasil penelitian menunjukkan visual connection yang terbentuk pada koridor ini didominasi bangunan komersial, sehingga memberikan image bangunan arsitektur modern yang mendominasi tampilan fasad bangunan. Hal ini masih sangat jauh dari apa yang diharapkan dari wajah kota Denpasar yang berwawasan budaya, namun dengan kondisi Koridor Jalan Teuku Umar yang merupakan salah satu pusat perdagangan dan jasa di Kota Denpasar. Diharapkan pada pengampu kebijakan yakni Pemerintah Kota Denpasar agar membuat acuan mengenai penggunaan fasad bangunan lebih khusus berdasarkan jenis fungsi bangunan dan tidak mengeneralisir sehingga pada fungsi bangunan komersial dapat menyesuaikan tampilan yang dapat menarik minat pengunjung dan juga sesuai dengan wajah kota yang diinginkan Kota Denpasar.
Kata kunci: fasad bangunan, visual connection, Koridor Jalan Teuku Umar Denpasar
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Agostinho Hernandez, Bruno, Harinderjit Singh Gill, and Sabina Gheduzzi. "A Novel Modelling Methodology Which Predicts the Structural Behaviour of Vertebral Bodies under Axial Impact Loading: A Finite Element and DIC Study." Materials 13, no. 19 (September 24, 2020): 4262. http://dx.doi.org/10.3390/ma13194262.
Повний текст джерелаАнотація:
Cervical spine injuries (CSIs) arising from collisions are uncommon in contact sports, such as rugby union, but their consequences can be devastating. Several FE modelling approaches are available in the literature, but a fully calibrated and validated FE modelling framework for cervical spines under compressive dynamic-impact loading is still lacking and material properties are not adequately calibrated for such events. This study aimed to develop and validate a methodology for specimen-specific FE modelling of vertebral bodies under impact loading. Thirty-five (n = 35) individual vertebral bodies (VBs) were dissected from porcine spine segments, potted in bone cement and μCT scanned. A speckle pattern was applied to the anterior faces of the bones to allow digital image correlation (DIC), which monitored the surface displacements. Twenty-seven (n = 27) VBs were quasi-statically compressively tested to a load up to 10 kN from the cranial side. Specimen-specific FE models were developed for fourteen (n = 14) of the samples in this group. The material properties were optimised based on the experimental load-displacement data using a specimen-specific factor (kGSstatic) to calibrate a density to Young’s modulus relationship. The average calibration factor arising from this group was calculated (K¯GSstatic) and applied to a control group of thirteen (n = 13) samples. The resulting VB stiffnesses was compared to experimental findings. The final eight (n = 8) VBs were subjected to an impact load applied via a falling mass of 7.4kg at a velocity of 3.1ms−1. Surface displacements and strains were acquired from the anterior VB surface via DIC, and the impact load was monitored with two load cells. Specimen-specific FE models were created for this dynamic group and material properties were assigned again based on the density–Young’s modulus relationship previously validated for static experiments, supplemented with an additional factor (KGSdynamic). The optimised conversion factor for quasi-static loading, K¯GSstatic, had an average of 0.033. Using this factor, the validation models presented an average numerical stiffness value 3.72% greater than the experimental one. From the dynamic loading experiments, the value for KGSdynamic was found to be 0.14, 4.2 times greater than K¯GSstatic. The average numerical stiffness was 2.3% greater than in the experiments. Almost all models presented similar stiffness variations and regions of maximum displacement to those observed via DIC. The developed FE modelling methodology allowed the creation of models which predicted both static and dynamic behaviour of VBs. Deformation patterns on the VB surfaces were acquired from the FE models and compared to DIC data, achieving high agreement. This methodology is now validated to be fully applied to create whole cervical spine models to simulate axial impact scenarios replicating rugby collision events.
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Coibion, Olivier, Yuriy Gorodnichenko, Saten Kumar, and Jane Ryngaert. "Do You Know that I Know that You Know…? Higher-Order Beliefs in Survey Data*." Quarterly Journal of Economics, January 30, 2021. http://dx.doi.org/10.1093/qje/qjab005.
Повний текст джерелаАнотація:
Abstract We implement a new survey of firms, focusing on their higher-order macroeconomic expectations. The survey provides a novel set of stylized facts regarding the relationship between first-order and higher-order expectations of economic agents, including how they adjust their beliefs in response to a variety of information treatments. We show how these facts can be used to calibrate key parameters of noisy-information models with infinite regress as well as to test predictions made by this class of models. We also consider a range of extensions to the basic noisy-information model that can potentially better reconcile theory and empirics. Although some extensions like level-k thinking are unsuccessful, incorporating heterogeneous long-run priors can address the empirical shortcomings of the basic noisy-information model.
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Dai, Tiantian, Xiangbo Liu, and Wei Sun. "The effects of monetary policy on input inventories." B.E. Journal of Macroeconomics 20, no. 1 (April 8, 2019). http://dx.doi.org/10.1515/bejm-2017-0251.
Повний текст джерелаАнотація:
Abstract This paper explores both the long-run and short-run effects of monetary policy on input inventories in a search model with monetary propagation and two-stage production. Inventories arise endogenously due to search frictions. In the long run, we analytically show that an increase in the money growth rate has hump-shaped real effects on steady-state input inventory investment, input inventory-to-sales ratio as well as sales. These effects are driven by both the extensive and intensive margins in the finished goods market. We then calibrate the model to the US data to study the short-run effects of monetary policy. We first show that our model can reproduce the stylized facts of input inventories quite well and then find that input inventories amplify aggregate fluctuations over business cycles.
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Pham Xuan, Rebecca, Lena M. Andreessen, and Thorsten O. Zander. "Investigating the Single Trial Detectability of Cognitive Face Processing by a Passive Brain-Computer Interface." Frontiers in Neuroergonomics 2 (April 8, 2022). http://dx.doi.org/10.3389/fnrgo.2021.754472.
Повний текст джерелаАнотація:
An automated recognition of faces enables machines to visually identify a person and to gain access to non-verbal communication, including mimicry. Different approaches in lab settings or controlled realistic environments provided evidence that automated face detection and recognition can work in principle, although applications in complex real-world scenarios pose a different kind of problem that could not be solved yet. Specifically, in autonomous driving—it would be beneficial if the car could identify non-verbal communication of pedestrians or other drivers, as it is a common way of communication in daily traffic. Automated identification from observation whether pedestrians or other drivers communicate through subtle cues in mimicry is an unsolved problem so far, as intent and other cognitive factors are hard to derive from observation. In contrast, communicating persons usually have clear understanding whether they communicate or not, and such information is represented in their mindsets. This work investigates whether the mental processing of faces can be identified through means of a Passive Brain-Computer Interface (pBCI). This then could be used to support the cars' autonomous interpretation of facial mimicry of pedestrians to identify non-verbal communication. Furthermore, the attentive driver can be utilized as a sensor to improve the context awareness of the car in partly automated driving. This work presents a laboratory study in which a pBCI is calibrated to detect responses of the fusiform gyrus in the electroencephalogram (EEG), reflecting face recognition. Participants were shown pictures from three different categories: faces, abstracts, and houses evoking different responses used to calibrate the pBCI. The resulting classifier could distinguish responses to faces from that evoked by other stimuli with accuracy above 70%, in a single trial. Further analysis of the classification approach and the underlying data identified activation patterns in the EEG that corresponds to face recognition in the fusiform gyrus. The resulting pBCI approach is promising as it shows better-than-random accuracy and is based on relevant and intended brain responses. Future research has to investigate whether it can be transferred from the laboratory to the real world and how it can be implemented into artificial intelligences, as used in autonomous driving.
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Okhmak, Valeriia Mykolaivna, and Artem V. Krylov. "Internet of Things Technology of Imagine Processing for Smart House." Electronic and Acoustic Engineering 4, no. 4 (December 23, 2021). http://dx.doi.org/10.20535/2617-0965.eae.229910.
Повний текст джерелаАнотація:
The article considers the image processing, detection of human faces and the transfer of relevant information in MATLAB software. During the rapid global process of industrialization and globalization, elements of smart homes for personal use are becoming popular in production and offices. Life and personal information security is the most important requirement and task of current and future Internet of Things solutions. Therefore, the system of recognizing objects, including people, is relevant and still one that can be qualitatively improved. The processing begins with a state file, which can be replaced by real-time systems, after receiving information from video — is selected in groups of points, which are the corresponding arrays of information. Arrays contains numbers which indicate whether a human face in front of the camera. The data is calibrated to avoid false detection with median distribution. As a result of involving graphic additions, the user can observe in real time where and how many faces are in front of the camera. MATLAB was chosen as the programming environment, because the program includes built-in blocks that allow you to easily combine the mathematical and applied part of the proposed solution. As a result of modeling a complex model was obtained that is able to process the image and determine the necessary elements and objects in the image. This model can be used to track changes in position in space, any, object or objects depending on their size or physical characteristics. A feature of the proposed method is the ability to calibrate and optimize the mathematical model depending on the physical parameters of the system and the required information at the output of the system.
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Du, Hang, Hailin Shi, Dan Zeng, Xiao-Ping Zhang, and Tao Mei. "The Elements of End-to-end Deep Face Recognition: A Survey of Recent Advances." ACM Computing Surveys, January 5, 2022. http://dx.doi.org/10.1145/3507902.
Повний текст джерелаАнотація:
Face recognition is one of the most popular and long-standing topics in computer vision. With the recent development of deep learning techniques and large-scale datasets, deep face recognition has made remarkable progress and been widely used in many real-world applications. Given a natural image or video frame as input, an end-to-end deep face recognition system outputs the face feature for recognition. To achieve this, a typical end-to-end system is built with three key elements: face detection, face alignment, and face representation. The face detection locates faces in the image or frame. Then, the face alignment is proceeded to calibrate the faces to the canonical view and crop them with a normalized pixel size. Finally, in the stage of face representation, the discriminative features are extracted from the aligned face for recognition. Nowadays, all of the three elements are fulfilled by the technique of deep convolutional neural network. In this survey article, we present a comprehensive review about the recent advance of each element of the end-to-end deep face recognition, since the thriving deep learning techniques have greatly improved the capability of them. To start with, we present an overview of the end-to-end deep face recognition. Then, we review the advance of each element, respectively, covering many aspects such as the to-date algorithm designs, evaluation metrics, datasets, performance comparison, existing challenges, and promising directions for future research. Also, we provide a detailed discussion about the effect of each element on its subsequent elements and the holistic system. Through this survey, we wish to bring contributions in two aspects: first, readers can conveniently identify the methods which are quite strong-baseline style in the subcategory for further exploration; second, one can also employ suitable methods for establishing a state-of-the-art end-to-end face recognition system from scratch.
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Kromp, F., B. Balaban, V. Cottin, I. Cuevas Saiz, P. Fancsovits, M. Fawzy, N. Findikli, et al. "O-285 Artificial intelligence algorithms reach expert-level accuracy in automated grading of blastocyst morphology assessment based on static embryo images and Gardner criteria." Human Reproduction 37, Supplement_1 (June 29, 2022). http://dx.doi.org/10.1093/humrep/deac106.078.
Повний текст джерелаАнотація:
Abstract Study question Can artificial intelligence (AI) algorithms reach expert-level accuracy in blastocyst morphology assessment according to Gardner criteria? Summary answer The prediction accuracy of the best performing AI algorithm (Deit), outperformed human-level mean accuracies compared to an embryologist majority vote for all Gardner morphological criteria. What is known already Routinely, morphological grading of blastocysts is performed visually according to Gardner criteria, which suggest expansion (EXP), quality of inner cell mass (ICM), and trophectoderm (TE) as key parameters to predict treatment outcome. Consequently, blastocyst scoring is prone to inter-and intra-observer variability, which may lead to inconsistencies in selecting blastocysts for transfer. AI-based algorithms may help to improve treatment outcome predictability, as it has been suggested recently. In those studies, parameters such as blastocyst quality or stage were annotated by experts from static or time-lapse-derived blastocyst images, to train AI algorithms, e.g. XCeption or YOLO, and compare them to human annotators. Study design, size, duration This retrospective study involves 2,270 images from 837 patients collected over a period of four years in a university IVF clinic. Participants/materials, setting, methods All images were annotated by one senior embryologist and divided into a training and a balanced test set. Subsequently, eight embryologists labeled 300 test set images such that every single image was seen by at least four embryologists. Annotators diverging from the ensemble vote for more than one standard deviation were excluded (n = 2) to set the ground truth labels. Finally, three AI architectures (XCeption, Swin, Deit) were trained and evaluated on that particular ground truth. Main results and the role of chance Out of nine annotators, labelling accuracy of two embryologists diverged from the consensus vote for more than one standard deviation for at least one of the three Gardner criteria. The consensus vote was built from the remaining seven annotators (mean accuracy EXP 0.81, ICM 0.70, TE 0.67). The Swin architecture outperformed the mean expert accuracy for all three criteria (EXP 0.82, ICM 0.76, TE 0.68), while the Deit and the XCeption architecture outperformed the mean expert accuracy in ICM accuracy (Deit 0.72, XCeption 0.73), and performed equal or worse in EXP and TE accuracy (Deit EXP 0.77, ICM 0.73; XCeption EXP 0.77, TE 0.66). When compared to a recent study conducted on time-lapse imaging data using AI algorithms, all our models outperform the ICM accuracy and achieve comparable TE accuracy. To minimize the role of chance in calculating the models' prediction accuracies, the SWA-Gaussian (SWAG) algorithm was used. SWAG is a method to reflect and calibrate uncertainty representation in Bayesian deep learning. It is based on modelling a Gaussian distribution for each networks' weight and applying it as a posterior over all neural network weights to perform Bayesian model averaging. Limitations, reasons for caution To reflect a real IVF lab scenario, embryologists of different origins and levels of experience were involved and no scoring training was offered to the participants. These facts could have potentially negatively affected the degree of consensus, although we excluded two annotators diverging from the mean labeling accuracy. Wider implications of the findings In the past, AI algorithms proved to reliably differentiate between good and bad prognosis blastocysts but not necessarily between blastocysts of similar quality. Further AI-supported differentiation on the basis of expansion and cell lineages will facilitate the ranking of blastocysts and would bring automated scoring closer to clinical application. Trial registration number Not applicable.