Accurate Representation
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2022 ◽  
Vol 14 (2) ◽  
pp. 375
Author(s):  
Sina Voshtani ◽  
Richard Ménard ◽  
Thomas W. Walker ◽  
Amir Hakami

We applied the parametric variance Kalman filter (PvKF) data assimilation designed in Part I of this two-part paper to GOSAT methane observations with the hemispheric version of CMAQ to obtain the methane field (i.e., optimized analysis) with its error variance. Although the Kalman filter computes error covariances, the optimality depends on how these covariances reflect the true error statistics. To achieve more accurate representation, we optimize the global variance parameters, including correlation length scales and observation errors, based on a cross-validation cost function. The model and the initial error are then estimated according to the normalized variance matching diagnostic, also to maintain a stable analysis error variance over time. The assimilation results in April 2010 are validated against independent surface and aircraft observations. The statistics of the comparison of the model and analysis show a meaningful improvement against all four types of available observations. Having the advantage of continuous assimilation, we showed that the analysis also aims at pursuing the temporal variation of independent measurements, as opposed to the model. Finally, the performance of the PvKF assimilation in capturing the spatial structure of bias and uncertainty reduction across the Northern Hemisphere is examined, indicating the capability of analysis in addressing those biases originated, whether from inaccurate emissions or modelling error.


2022 ◽  
Author(s):  
Christopher M Pooley ◽  
Andrea B Doeschl-Wilson ◽  
Glenn Marion

Well parameterised epidemiological models including accurate representation of contacts, are fundamental to controlling epidemics. However, age-stratified contacts are typically estimated from pre-pandemic/peace-time surveys, even though interventions and public response likely alter contacts. Here we fit age-stratified models, including re-estimation of relative contact rates between age-classes, to public data describing the 2020-21 COVID-19 outbreak in England. This data includes age-stratified population size, cases, deaths, hospital admissions, and results from the Coronavirus Infection Survey (almost 9000 observations in all). Fitting stochastic compartmental models to such detailed data is extremely challenging, especially considering the large number of model parameters being estimated (over 150). An efficient new inference algorithm ABC-MBP combining existing Approximate Bayesian Computation (ABC) methodology with model-based proposals (MBP) is applied. Modified contact rates are inferred alongside time-varying reproduction numbers that quantify changes in overall transmission due to pandemic response, and age-stratified proportions of asymptomatic cases, hospitalisation rates and deaths. These inferences are robust to a range of assumptions including the values of parameters that cannot be estimated from available data. ABC-MBP is shown to enable reliable joint analysis of complex epidemiological data yielding consistent parametrisation of dynamic transmission models that can inform data-driven public health policy and interventions.


2022 ◽  
Author(s):  
Filippo Salustri

<div>There is mounting evidence in the current literature which suggests that our collective understanding of engineering design is insufficient to support the continued growth of the engineering endeavor. Design theory is the emergent research field that addresses this problem by seeking to improve our understanding of, and thus our ability to, design. The goal of this author's work is to demonstrate that formal techniques of logic can improve our understanding of design. Specifically, a formal system called the Hybrid Model (HM) is presented; this system is a set-theoretic description of engineering design information that is valid independent of (a) the processes that generate or manipulate the information and (b) the role of the human designer. Because of this, HM is universally applicable to the representation of design-specific information throughout all aspects of the engineering enterprise. The fundamental unit in HM is a design entity, which is defined as a unit of information relevant to a design task. The axioms of HM define the structure of design entities and the explicit means by which they may be rationally organized. HM provides (a) a basis for building taxonomies of design entities, (b) a generalized approach for making statements about design entities independent of how the entities are generated or used, and (c) a formal syntactic notation for the standardization of design entity specification. Furthermore, HM is used as the foundation of DESIGNER, an extension to the Scheme programming language, providing a prototype-based object-oriented system for the static modeling of design information. Objects in the DESIGNER language satisfy the axioms of HM while providing convenient programming mechanisms to increase usability and efficiency. Several design-specific examples demonstrate the applicability of DESIGNER, and thus of HM as well, to the accurate representation of design information. </div>


2022 ◽  
Author(s):  
Filippo Salustri

<div>There is mounting evidence in the current literature which suggests that our collective understanding of engineering design is insufficient to support the continued growth of the engineering endeavor. Design theory is the emergent research field that addresses this problem by seeking to improve our understanding of, and thus our ability to, design. The goal of this author's work is to demonstrate that formal techniques of logic can improve our understanding of design. Specifically, a formal system called the Hybrid Model (HM) is presented; this system is a set-theoretic description of engineering design information that is valid independent of (a) the processes that generate or manipulate the information and (b) the role of the human designer. Because of this, HM is universally applicable to the representation of design-specific information throughout all aspects of the engineering enterprise. The fundamental unit in HM is a design entity, which is defined as a unit of information relevant to a design task. The axioms of HM define the structure of design entities and the explicit means by which they may be rationally organized. HM provides (a) a basis for building taxonomies of design entities, (b) a generalized approach for making statements about design entities independent of how the entities are generated or used, and (c) a formal syntactic notation for the standardization of design entity specification. Furthermore, HM is used as the foundation of DESIGNER, an extension to the Scheme programming language, providing a prototype-based object-oriented system for the static modeling of design information. Objects in the DESIGNER language satisfy the axioms of HM while providing convenient programming mechanisms to increase usability and efficiency. Several design-specific examples demonstrate the applicability of DESIGNER, and thus of HM as well, to the accurate representation of design information. </div>


F1000Research ◽  
2022 ◽  
Vol 11 ◽  
pp. 13
Author(s):  
Chakrapani Mahabala ◽  
Pradeepa H. Dakappa ◽  
Arjun R. Gupta

Background: Sublingual temperature measurement is a quick and accurate representation of oral temperature and corresponds closely with core temperature. Sub-lingual temperature measurement using non-contact infrared thermometers has not been studied for this purpose and if accurate they would be a reliable and convenient way of recording temperature of a patient very quickly. The aim of the study was to evaluate the utility of recording sublingual temperature using an infrared non-contact thermometer and establish its accuracy by comparing the readings with tympanic thermometer recordings. Methods: This cross-sectional study was carried out in 29 patients (328 paired recordings from sublingual and tympanic sites simultaneously). Subjects were requested to keep their mouth closed for five minutes before recording the temperature. Sublingual recordings were performed for each patient at different times of the day using an infrared thermometer. The infrared thermometer was quickly brought 1cm away from the sublingual part of the tongue and the recordings were then done immediately. Readings were compared with the corresponding tympanic temperature. Results: The non-contact sublingual temperature correlated very closely with tympanic temperature (r=0.86, p<0.001). The mean difference between the infrared sublingual and tympanic temperature was 0.21°C (standard deviation [SD]:0.48°C, 95% confidence interval [CI] of 0.16-0.27). The intra-class correlation co-efficient (ICC) between core and sublingual temperatures was 0.830 (95% CI: 0.794 to 0.861) p<0.001. The sensitivity of sublingual IR (infrared) temperature of 37.65°C was 90% and specificity was 89% for core temperature >38°C. Conclusions: This innovative modification of using the forehead infrared thermometer to measure the sublingual temperature offers an accurate, rapid and non-contact estimation of core temperature.


2022 ◽  
Vol 23 (1) ◽  
pp. 200-221
Author(s):  
Azhar Mohd Ibrahim ◽  
Muhammad Arif Kamaruddin ◽  
Azni Nabela Wahid

Every year, many disasters occur to buildings causing their destruction and leading to huge casualties. One way of preventing casualties is by evacuation drill activity. Although accurate evacuation drills could enhance the efficiency of the process during the real event, these drills are not fully effective because participants miss the sense of being stressed or under pressure while in action. Several gaming concepts have been introduced to train the participants on how to cope with and evacuate effectively during an emergency. For instance, Augmented Reality (AR) and Virtual Reality (VR) interfaces could provide virtual content to enhance the effectiveness of evacuation drills. However, accurate representation of different evacuation scenarios and its impact analysis during emergency using the above technologies are still debatable, mainly due to immersion quality. Thus, this study proposes an Immersive Augmented Reality (IAR) application that is mainly the amalgamation of AR and VR in realizing fast and safe evacuation during on-site building emergencies. A virtual dynamic exit signage system is also developed in the proposed “Smart Evacuation application“. This work evaluated the efficiency of a virtual dynamic exit signage and also a proposed “Smart Evacuation“ system by analysing on-site emergency evacuation processes. By setting up various scenarios imitating real life disasters, this research analysed the time taken and level of stress of the occupants during the evacuation of a chosen site. The proposed “Smart Evacution“ achieved 33.82% better perfomance compared to normal evacuation thus indicating a faster and safer evacuation. ABSTRAK: Secara statistik, kebanyakan bencana kemusnahan bangunan yang berlaku setiap tahun telah menyebabkan kerugian besar. Salah satu cara bagi mengelak kejadian ini adalah melalui aktiviti latih tubi evakuasi. Walaupun latih tubi evakuasi ini dapat menambah proses kecekapan semasa kejadian sebenar, latih tubi ini tidak benar-benar berkesan kerana peserta kurang mendalami perasaan tertekan atau di bawah tekanan semasa kejadian. Pelbagai konsep permainan telah diperkenalkan bagi melatih peserta bagaimana perlu bertindak dan evakuasi secara efektif semasa kecemasan. Sebagai contoh, antarmuka Realiti Terimbuh (AR) dan Realiti Maya (VR) mungkin dapat menghasilkan simulasi secara maya bagi menambah keberkesanan latih tubi evakuasi. Walau bagaimanapun, ketepatan representasi pelbagai senario evakuasi dan analisis tekanan semasa kecemasan menggunakan teknik-teknik di atas adalah masih boleh dipertikaikan terutama kerana kualiti kedalamannya. Oleh itu, kajian ini mencadangkan aplikasi Realiti Terimbuh Mendalam (IAR) di mana tumpuan adalah pada kombinasi AR dan VR dibuat dengan secara evakuasi pantas dan selamat semasa kecemasan pada bangunan kejadian. Sistem maya penunjuk arah keluar dinamik turut dicipta dalam “Aplikasi Evakuasi Pintar” yang dicadangkan ini. Kajian ini menilai keberkesanan sistem maya penunjuk arah keluar secara dinamik dan juga sistem “Evakuasi Pintar” dengan menganalisa proses evakuasi kecemasan pada tempat kejadian. Dengan mengadakan pelbagai jenis senario dan meniru bencana sebenar, kajian ini menganalisa masa yang diambil dan tahap tekanan penghuni bangunan semasa proses evakuasi berlaku pada tapak pilihan. “Evakuasi Pintar” ini mencapai 33.82% keberkesanan pada prestasi berbanding evakuasi biasa. Ia membuktikan proses evakuasi ini lebih pantas dan selamat.


2022 ◽  
Vol 258 ◽  
pp. 07002
Author(s):  
Pantelis Pnigouras ◽  
Nils Andersson ◽  
Andrea Passamonti

During the late stages of a neutron star binary inspiral finite-size effects come into play, with the tidal deformability of the supranuclear density matter leaving an imprint on the gravitational-wave signal. As demonstrated in the case of GW170817—the first direct detection of gravitational waves from a neutron star binary—this can lead to strong constraints on the neutron star equation of state. As detectors become more sensitive, effects which may have a smaller influence on the neutron star tidal deformability need to be taken into consideration. Dynamical effects, such as oscillation mode resonances triggered by the orbital motion, have been shown to contribute to the tidal deformability, especially close to the neutron star coalesence, where current detectors are most sensitive. We calculate the contribution of the various stellar oscillation modes to the tidal deformability and demonstrate the (anticipated) dominance of the fundamental mode. We show what the impact of the matter composition is on the tidal deformability, as well as the changes induced by more realistic additions to the problem, e.g. the presence of an elastic crust. Finally, based on this formulation, we develop a simple phenomenological model describing the effective tidal deformability of neutron stars and show that it provides a surprisingly accurate representation of the dynamical tide close to merger.


2021 ◽  
Vol 2 (6) ◽  
pp. 1-12
Author(s):  
Menduza Burnd ◽  
Joffersen Yrick

The aims of the research is determine the Product Preservation Design of Vegetable and Animal Food Processing. Packaging designed to preserve food components in the hands of customers while preventing contamination by bacteria and fungus is the goal. As long as food is stored properly, the quality of the food will deteriorate. Packaging is necessary in order to deliver the following information: Package must convey an accurate representation of its contents; it should neither be copied from other parties' packaging designs, nor should it be too complex, making it prohibitively costly to produce


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Arup Varma ◽  
Satish Kumar ◽  
Riya Sureka ◽  
Weng Marc Lim

PurposeCareer Development International (CDI) is an established source of scientific research on careers and development. The journal reached its 25-years milestone in 2021. To commemorate the occasion, the article aims to provide a retrospective of the major trends, research constituents, thematic structure and key factors explaining the citation impact of CDI articles between 1996 and 2020.Design/methodology/approachThe article extracts bibliographic data of CDI from Scopus and uses that data in (1) a series of bibliometric analyses to explain the major trends, research constituents and thematic structure and (2) a negative binomial regression analysis to explain the key factors affecting the citation impact of CDI.FindingsThe article finds that CDI has progressed and contributed substantially to the scientific community since its inception 25 years ago. The contributions in CDI are mainly from America and Europe and can be organized around five major clusters, namely career development, work engagement, entrepreneurship career, career outcomes and career mentoring.Research limitations/implicationsThe article provides a rich overview of CDI, but the findings are limited to the accuracy and availability of bibliographic data of CDI from Scopus.Originality/valueThe article extends Akkermans and Kubasch's (2017) 5-years retrospection of major journals on career and development through a 25-years retrospection of CDI, and in doing so, the article provides a longer and more accurate representation of CDI's contributions to the extant literature on career and development.


2021 ◽  
Vol 18 (24) ◽  
pp. 6547-6565
Author(s):  
Linda M. J. Kooijmans ◽  
Ara Cho ◽  
Jin Ma ◽  
Aleya Kaushik ◽  
Katherine D. Haynes ◽  
...  

Abstract. The uptake of carbonyl sulfide (COS) by terrestrial plants is linked to photosynthetic uptake of CO2 as these gases partly share the same uptake pathway. Applying COS as a photosynthesis tracer in models requires an accurate representation of biosphere COS fluxes, but these models have not been extensively evaluated against field observations of COS fluxes. In this paper, the COS flux as simulated by the Simple Biosphere Model, version 4 (SiB4), is updated with the latest mechanistic insights and evaluated with site observations from different biomes: one evergreen needleleaf forest, two deciduous broadleaf forests, three grasslands, and two crop fields spread over Europe and North America. We improved SiB4 in several ways to improve its representation of COS. To account for the effect of atmospheric COS mole fractions on COS biosphere uptake, we replaced the fixed atmospheric COS mole fraction boundary condition originally used in SiB4 with spatially and temporally varying COS mole fraction fields. Seasonal amplitudes of COS mole fractions are ∼50–200 ppt at the investigated sites with a minimum mole fraction in the late growing season. Incorporating seasonal variability into the model reduces COS uptake rates in the late growing season, allowing better agreement with observations. We also replaced the empirical soil COS uptake model in SiB4 with a mechanistic model that represents both uptake and production of COS in soils, which improves the match with observations over agricultural fields and fertilized grassland soils. The improved version of SiB4 was capable of simulating the diurnal and seasonal variation in COS fluxes in the boreal, temperate, and Mediterranean region. Nonetheless, the daytime vegetation COS flux is underestimated on average by 8±27 %, albeit with large variability across sites. On a global scale, our model modifications decreased the modeled COS terrestrial biosphere sink from 922 Gg S yr−1 in the original SiB4 to 753 Gg S yr−1 in the updated version. The largest decrease in fluxes was driven by lower atmospheric COS mole fractions over regions with high productivity, which highlights the importance of accounting for variations in atmospheric COS mole fractions. The change to a different soil model, on the other hand, had a relatively small effect on the global biosphere COS sink. The secondary role of the modeled soil component in the global COS budget supports the use of COS as a global photosynthesis tracer. A more accurate representation of COS uptake in SiB4 should allow for improved application of atmospheric COS as a tracer of local- to global-scale terrestrial photosynthesis.


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