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Equilibrium climate sensitivity (ECS) is defined as the change in the global mean surface air temperature due to the doubling or quadrupling of CO2 in a climate model simulation. This metric is used to determine the uncertainty in future climate projections, and therefore, the impact of model changes on ECS is of large interest to the climate modeling community. In this paper, we propose a new graphical method, which is an extension of Gregory's linear regression method, to represent the impact of model changes on ECS, climate forcing, and climate feedbacks in a single diagram. Using this visualization method, one can (a) quantify whether the model or process change amplifies, reduces, or has no impact on global warming, (b) evaluate the percentage changes in ECS, climate forcing, and climate feedbacks, and (c) quantify the ranges of the uncertainties in the estimated changes. We demonstrate this method using an example of climate sensitivity simulations with and without interactive chemistry. This method can be useful for multimodel assessments where the response of multiple models for the same model experiment (e.g., usage of interactive chemistry compared with the prescribed chemistry as shown here) can be assessed simultaneously, which is otherwise difficult to compare and comprehend. We also demonstrate how this method can be used to examine the spread in ECS, climate forcing, and climate feedbacks with respect to the multimodel mean (or one benchmark model) for multimodel frameworks such as Coupled Model Intercomparison Project Phase 5 or for different ensemble members in a large ensemble of simulations conducted using a single model. [ABSTRACT FROM AUTHOR]

This paper is devoted to the problem of pauses detection in English speech signals. The aim of the current study is to create a new method of speech pauses detection that has no drawbacks other algorithms suffer from. The analysis of it suggests the opportunity to use the graphical method in real-time applications. The article provides a new vision and a new solution of pauses detection problem. The result of the study - the graphical method - may be applied to real-time signal processing, text-to-speech synthesis or used to enrich knowledge about the specified problems. [ABSTRACT FROM AUTHOR]

We present a nontrigonometric graphical method for predicting the trajectory of a projectile when the angle and initial velocity are known. Students enrolled in a general education conceptual physics course typically have weak backgrounds in trigonometry, making inaccessible the standard analytical calculation of projectile range. Furthermore, research shows that standard instructional techniques fail to confront student misconceptions about motion in a gravitational field. We have designed a guided inquiry-based lesson that specifically addresses these misconceptions with minimal mathematics.

Industrial sectors are improving their energy efficiency and increasing their share of renewables for heating and cooling demands by using lower emission technologies. One specific approach to help achieve these targets is the integration of heat pumps (HPs) in industrial processes. However, due to the temporal variation of the heating and cooling requirements in non-continuous processes, the integration of HP is challenging. In this paper, a structured method for the design of HP integration is proposed. The method implements an engineer-centred workflow that extends the concept of the Indirect Source Sink Profile (ISSP) to HP integration. For this purpose, an adapted Grand Composite Curve is derived from the ISSP. This ensures correct HP integration across the pinch while maintaining the temperature lift of the HP small. The proposed workflow is applied to a demonstration case study and a case study from industry. In both cases, the resulting system with integrated HP enables the elimination of hot utility demand and significantly reduces cold utility demands. The static paybacks of the proposed solutions are in the range of 4.5 to 5 year. [ABSTRACT FROM AUTHOR]

Research on graphical methods of reasoning has made enormous progress since the pioneering work of Wigmore in the early 20th century and its later rediscovery in the 1980s. While the usefulness of graphical methods for student training and research is widely acknowledged, their use by judges remains marginal, if not non-existent, even though this was Wigmore's objective. This article explores the difficulties that graphical methods of reasoning must overcome if they are to be integrated into the practice of the courts, at a time when courts are faced with ever more pressing imperatives of efficiency. The research is based on a partnership with the French School of Magistrates (Ecole Nationale de la Magistrature) and is informed by training courses given to magistrates on the basis of real cases, during which the authors proposed that they implement what we have called the Orderly Method of Evidence Analysis. Although the research confirms the value of graphical methods in promoting rigour in evidential reasoning, it also reaffirms the already clearly identified limits related to their complexity and time-consuming nature. The article also points out the difficulties that still need to be overcome in order to operationalise graphical methods of evidential reasoning, and the difficulties encountered by these methods in avoiding judgment bias. [ABSTRACT FROM AUTHOR]

Ensuring fire safety is an important function of the state, which includes a set of measures to ensure the prevention of fires, their direct suppression and the conduct of rescue operations at the site.This article deals with the problems of providing instructions on fire safety. Based on the synthesis of the functions of the fire safety system, the tasks of the fire department and the statistical data of appeals to the fire service, as well as the provisions of the Federal Law of the Russian Federation, an idea was put forward to solve these problems. On the basis of the organization and implementation of fire prevention, which included conducting briefings and special classes with workers and employees of the fire safety facility, as well as other persons potentially associated with the occurrence of a fire, an operation was conducted to simulate a graphical presentation of fire safety briefings. Using the methodology of V.G. Burlov, the effectiveness of the use of improved fire safety instruction was proved.

A simple graphical method for marking ordering questions that are partially correct is presented in this paper. The method is based on a strategy proposed by Lisle (1993). The application of the method to the marking of ordering questions and some of the wider issues associated with marking ordering questions are discussed. [ABSTRACT FROM AUTHOR]

We propose a powerful graphical method for evaluating the natural complex frequencies and amplitudes of the layered structures for their electromagnetic characterization. Its advantage is to show a pattern of the location of the natural complex frequencies so that it would be possible to examine how they can move for a possible error in the measurement system. The method is validated by a two-layered structure by comparing the natural complex frequencies and amplitudes computed by the proposed method and the inverse Fourier transform. It has been applied to monitor the effect of noise in a measurement system. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) funicular structures can be easily generated and controlled by means of simple geometric constructions. These geometric constructions derive from reciprocal relationships between the form and force diagrams of a structure, which form the basis of graphic statics. Unlike in 2D space, in 3D space, similar geometric constructions cannot always be established for the design of three‐dimensional (3D) funicular structures. In some specific cases though, purely geometric procedures requiring no numerical approximations can be defined. In particular, this contribution explores the geometric transformation of 2D funicular structures as a means to graphically generate 3D funicular structures in equilibrium with coplanar loads. A fully graphical method for the construction of such pairs of 3D skew funiculars in equilibrium with coplanar loads and with control over the position of the supports is presented. It is based on geometrical linear relationships between the original and the transformed structures. Ultimately, it is shown how such pairs of 3D skew funiculars can be applied to the design of bridge and roof structures for instance. [ABSTRACT FROM AUTHOR]

This research proposes a new graphical method for the analysis of heat recovery systems, applicable to both phases of grassroots and revamping. The new graphical method is based on plotting temperatures of process hot streams versus temperatures of process cold streams. A new graph is constructed for representing existing preheat trains. For a given preheat train, each existing exchanger is represented by a straight line, whose slope is proportional to the ratio of heat capacities and flows. Further, the length of each exchanger line is related to the heat flow transferred across this exchanger. This new graphical representation can easily identify exchangers-across-the-pinch, Network Pinch, pinching matches and improper placement of fuel consumption. Furthermore, such a graph can recognise promising modifications to improve the energy performance and hence less fuel and cooling water requirement. Graphs developed in this work can be used to analyse the energy performance of existing networks with respect to energy targets. They can also be used in junction with the background process to modify basic designs or existing network for better energy integration opportunities and minimum fuel demands.

Heat exchanger networks (HENs) play a significant role in the energy conservation of any process industry. The HENs are used to maximize heat recovery by exchanging heat between hot and cold process streams. Therefore, the optimum design of HENs is extremely important to reach the maximum efficiency of energy systems. Many graphical methods have been developed during the last four decades for synthesizing of heat exchanger networks (HENs). However, most of these methods have only been evaluated for retrofitting design of HENs. In the grassroots design situation, these methods are often complicated and tedious. This paper introduces a new and simple graphical approach for HEN grassroots design. The new approach based on a single graph called Supply-Target Diagram (STD). The ST-D is formulated by plotting supply temperatures versus target temperatures of streams. Streams matching can easily be applied in the ST-D and splitting of streams is clearly visualized and evaluated. A case study is used to illustrate the application of the new graphical method for grassroots design of HENs. [ABSTRACT FROM AUTHOR]

Increasing effort of solar power integration to the grid could be accelerated towards sustainability goal. However, high PV penetration ratio (PVR) in turn critically reduces system frequency response performance of an existing power system due to reduction of on‐line rotating generators. Besides intrinsic system inertia, system RC plays a vital role in dynamically securing the power system operation subject to large PV disturbances. This study proposes a graphical method to determine critical values of system RC requirement with respect to the anticipated PVR and PV ramp‐down rate of disturbance; both of which should be forecastable, in practice, in each operating time interval. Impact of PVR on dynamic performance of a power system, through the effective time‐varying of system inertia and governor response characteristic has been examined. The results of the analyses on graphical display will be useful for system operators to prepare enough system RC, economically well in‐advance through Unit Commitment program, to ensure system dynamic security, complying with the N‐1 contingency constraint. In addition, the proposed graphical display can reveal whether the curtailment of aggregated PV's output generation is necessary for that time interval. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

As a promising green technology, Integrated Gasification Combined Cycle (IGCC) plant is more efficient and low-pollution electricity generation choice than conventional thermal power plants. Its process is mainly consist of the gasifier, the air separation unit and the combined cycle unit. Going through those key blocks, the fuel, such as coal and biomass, could be converted to syngas and further combusted for power generation. In order to be a viable technology, the bottleneck is located on the high energy production cost, which could be overcame by improving the plant efficiency through process optimisation and Integration. The opportunity and challenge are given by the complicated configuration and extreme operation conditions, which also demands a flexible and robust IGCC plant simulation to complete deep process analysis. In this work, a novel simplified IGCC mathematical model is proposed considering thermodynamics constraints with energy and mass conservation. The gasification is simulated based on the principle of Gibbs free energy minimisation, which holds the good feature of avoiding potential bi-level optimisation problem. The proposed gasification model results in syngas composition similar to the experimental data provided in literature. Meanwhile, the cryogenic air separation unit is selected with the double distillation column configuration, which is simulated considering the novel simplification of thermal coupled distillation columns. What is more, the combined cycle unit is simulated with isentropic assumption plus efficiency to complete the process. To validate the novel simplified IGCC model, one base case is built and compared with literature data. Another highlight of this work is the simultaneous optimisation and integration methodology instead of conventional sequential one, which gives more guarantee for achieving global optimal solution. If the ideal property assumptions are occupied, a graphical approach could be generated for the simultaneous optimization and integration of IGCC plant. The best material and energy integration scheme in proper operation condition could be selected considered with respect to the overall thermal efficiency of the IGCC plant. The good performance is shown by about 10 % power increment compared with the base case in the case study.

In the article we analyzed functionality of educational software supporting use of graphical method of secondary school algebra 7-9 forms problems solving - “TerM 7-9” [1, 2] and “Library of electronic visual aids. Algebra, 7-9 forms”

In demography, a detailed study of the temporal dynamics of the structure of a population is often required to better understand the processes that underline its overall dynamics and the individual’s life histories. Heatmaps, using time and structure (such as size-structure) as x and y coordinates and density as colours, are efficient tools for displaying the dynamics of a structured population. Such representations (structure-time diagrams) reveal the data at several levels, from general outlook to fine details. Despite its efficiency, this type of visual display has been scarcely used in ecology and demography. Using the example of springtail populations maintained in the laboratory and a woodlouse population studied in the field, we explain why this type of representation can be used to analyse the population dynamics of soil organisms and why it should be more widely used in demography. We also present the R package STdiag (for ‘Structure Time diagram’), an interface to complex graphical functions to easily produce and analyse such ‘structure-time diagrams’ from raw datasets. This package is available for all operating systems via R-Forge. Its syntax and options are described, discussed and illustrated using our case studies. This graphical display is a simple and efficient way to make large demographic datasets coherent and to disclose the underlying, often hidden, demographical processes.

The aim of the present study was to introduce Focused Principal Component Analysis (FPCA) as a novel exploratory method for providing insight into dietary patterns that emerge based on a given characteristic of the sample. To demonstrate the use of FPCA, we used a database of 1,968 adults. Food intake was obtained using a food frequency questionnaire covering 26 food items. The focus variables used for analysis were age, income, and schooling. All analyses were carried out using R software. The graphs generated show evidence of socioeconomic inequities in dietary patterns. Intake of whole-wheat foods, fruit, and vegetables was positively correlated with income and schooling, whereas for refined cereals, animal fats (lard), and white bread this correlation was negative. Age was inversely associated with intake of fast-food and processed foods and directly associated with a pattern that included fruit, green salads, and other vegetables. In an easy and direct fashion, FPCA allowed us to visualize dietary patterns based on a given focus variable.O presente estudo teve objetivo de apresentar a Análise de Componentes Principais Focada (ACPF) como um método exploratório para investigar padrões alimentares a partir de características da amostra. Para exemplificar utilizou-se as variáveis idade, renda e escolaridade de um banco de dados de 1.968 adultos. O consumo alimentar foi obtido através questionário de frequência alimentar (QFA) com 26 itens alimentares. As análises foram realizadas no programa R. Os gráficos gerados evidenciaram iniquidades socioeconômicas na conformação dos padrões alimentares. Alimentos integrais, frutas e verduras foram diretamente correlacionados com renda e escolaridade, e cereais refinados, gordura animal e pão branco tiveram associação inversa. A idade mostrou-se como associada inversamente a alimentos fast-food e industrializados e, diretamente, a um padrão "saudável" que inclui frutas, salada verde e outros vegetais. De maneira fácil e direta, a ACPF permitiu a visualização de correlações entre alimentos a partir de variáveis escolhidas como foco.