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The main purpose of this paper is to propose a new graphical method for a planetary gear train (PGT) analysis. This is a fully graphical method that determines the rotational speeds of all transmission components, as well as the torque, power flow, power losses, and efficiency of any PGT. With this method, a sketcher workbench available in any modern computer-aided design (CAD) system can be used. This provides an interactive way to work. Both the construction of the geometric model and the interpretation of the results are intuitive, which facilitates error identification. Observing the impact of the selected input data or model parameters on the model behavior is extremely easy and can even be animated. It is believed that the presented method can streamline the PGT design process.

Carbon dioxide emissions reduction has been a common trend for many industrial processes in recent years. However, few analytical tools have been developed for visualising CO2 emissions reduction and supporting decisions at the enterprise level. A graphical technique known as Carbon Emission Composite Curves was developed previously, but was limited to the production of single product. In this work, the CO2 emissions reduction procedure is focused and extended to multi-product plants, in which CO2 emissions of shared and dedicated facilities of the production line are analysed. For cases where the carbon intensity of shared facilities is higher than that of the dedicated facilities, CO2 emissions reduction should focus on the shared facilities, before efforts are put forward for the dedicated facilities. In contrast, when the carbon intensity of dedicated facilities is higher than that of the shared facilities, it is necessary to explore ways to reduce CO2 emissions of the dedicated facilities. Two case studies are used to illustrate the procedure.

A graphical method was developed to determine the six landmarks of pre-image population analysis (PPA) (Levins, 2000; Levins et al., 2013), using consecutive time series of abundance data. PPA offers an opportunity to assess the chance that a population exhibits chaotic dynamics, increasing the uncertainty of predictions and/or the success of management interventions. The proposed method was designed for the simplest non-linear difference equation [ x n + 1 = r x n ( 1 − x n ) ], a prerequisite of which is that the population describes a unimodal shape in the interval map, involving positive/negative self-feedback and a discontinuous breeding (discrete) pattern. Many different mathematical unimodal forms (shapes) and relations among landmarks can be found in the interval map. The unimodal shape was constructed through three segments: the first segment starts at zero on the xn axis and rises until the peak value; the second segment links the peak with the equilibrium value (∼average abundance); the last segment connects the equilibrium and 1.0 on the xn axis. The method was applied with two (not real) abundance data sets of one species inhabiting different habitats. Using this graphical method, it was analytically possible to determine that a similar man-made intervention could erase or cause chaotic population dynamics, helping identify when and to what extent we can intervene. We propose this method for PPA as a complementary tool, which can aid in single-species management decisions and the adoption of conservation practices.

The purpose of this study is to introduce and demonstrate a novel graphical method to determine effective bremsstrahlung focal spot size and shape of the therapeutic beam from a linear accelerator . The energy distribution within the beam spot allows in determining effective bremsstrahlung size and shape of beam spot. The transverse and radial dose profiles were measured for a range of field sizes in an isocentric setup. The Length of direct focal region (LDFR) on either side of profiles were determined through the de-convolution of dose profile. The graph plotted for LDFR versus field size helps in determining properties of beam spot. The dimensions of FWHM of effective bremsstrahlung focal spot were found elliptical in nature close to the order of 1 mm. This method allows determination of FWHM of the effective bremsstrahlung focal spot that fairly falls within the range of dimension of FWHM of beamspot published in literature.

Optimal design of the machining setup in terms of installed machines, cutting tools and process parameters is of paramount importance for every manufacturing company. In most of the metal cutting companies, all choices related to machine eligibility and cutting parameters selection typically come from heuristic approaches and follow supplier indications or base on the skill of experienced machine operators. More advanced solutions, such as model-based and virtual approaches, are adopted less frequently mainly due to the lack of these techniques in grasping the underlying knowledge successfully. Aim of this work is to introduce a synthetic graphical representation of machining centers and cutting tools capabilities, to provide an accessible way to evaluate the feasibility and close-to-limit conditions of the cutting process. Taking inspiration from previous scientific works from the measurement engineering field, a set of 2D and 3D graphs are presented to map machine, tools and process capabilities, as well as their obtainable manufacturing performances and expectable tool life. This approach synthesizes the nominal data coming from different sources (catalogues, database, tool model geometries etc.) and the real cutting tools parameters used during the production phase. Some examples are provided to show the potential of this graphical evaluation in supporting process planning and decision-making and in formalizing the machining setup knowledge. Further developments are devoted to extend the method to other manufacturing processes, including hybrid processes. At the same time, an in-process data gathering software will be integrated for building a solid database that can be used by an autonomous multi-technological process selector, as well as by a pre-process condition advisor in an Industry 4.0 oriented way.

The paper proposes a method of profiling the disk tool generating the helical groove of the female rotor of the compressor, on the basis of a complementary theorem of enveloping surfaces, e.g. theorem "Substitution Circles Family", whose principles are developed in analytical way. On the basis of this theorem is proposed a method developed in the graphical environment Auto-CAD, in purpose to design the disk tool for profiling the female rotor and also to determinate the front view profile of this rotor, screw compressor component. Has been also detailed a numerical example for a known built compressor.

A surge in a centrifugal compressor can cause critical damage to the compressor, resulting in large repair costs, so one of the most important considerations in the design of compressor systems is to prevent a surge. However, conventional methods to size recycle valves in anti-surge systems are limited in that the valve characteristics and time delay cannot be quantitatively considered. This paper suggested a short-cut graphical method to easily size the recycle valves in an anti-surge system by considering the valve characteristics, including the dead time, actuation time, and opening types. Dynamic simulations were carried out to verify the resulting size of the valves, and the results of the simulation showed that a surge could be avoided effectively and economically.

Background Neurite outgrowth is a metric widely used to assess the success of in vitro neural stem cell differentiation or neuron reprogramming protocols and to evaluate high-content screening assays for neural regenerative drug discovery. However, neurite measurements are tedious to perform manually, and there is a paucity of freely available, fully automated software to determine neurite measurements and neuron counting. To provide such a tool to the neurobiology, stem cell, cell engineering, and neuroregenerative communities, we developed an algorithm for performing high-throughput neurite analysis in immunofluorescent images. New method Given an input of paired neuronal nuclear and cytoskeletal microscopy images, the GAIN algorithm calculates neurite length statistics linked to individual cells or clusters of cells. It also provides an estimate of the number of nuclei in clusters of overlapping cells, thereby increasing the accuracy of neurite length statistics for higher confluency cultures. GAIN combines image processing for neuronal cell bodies and neurites with an algorithm for resolving neurite junctions. Results GAIN produces a table of neurite lengths from cell body to neurite tip per cell cluster in an image along with a count of cells per cluster. Comparison with existing methods GAIN’s performance compares favorably with the popular ImageJ plugin NeuriteTracer for counting neurons, and provides the added benefit of assigning neurites to their respective cell bodies. Conclusions In summary, GAIN provides a new tool to improve the robust assessment of neural cells by image-based analysis.

Adsorption carbon capture technology has been considered as one of the most promising technologies to control the CO2 level in the atmosphere. From the view of thermodynamics, the adsorbed-bulk gas phase equilibrium system should be well developed for accurately elaborating the mechanism of CO2 adsorption. Since thermodynamic properties of the adsorbed CO2 plays a significant role in the cyclic analysis of carbon capture technology, in this work, the Gibbs’ thermodynamic graphical method was extended to the expression of thermodynamic properties of the adsorbed CO2 as a specific case study. The 3-dimensional (3D) thermodynamic surface was established to determine the thermodynamic properties of the adsorbed CO2 in the thermodynamic equilibrium state. The temperature and pressure were treated as the individual variables to calculate the thermodynamic properties of the adsorbed CO2, including the adsorption capacity, chemical potential, entropy, and internal energy. Finally, the internal energy-adsorption capacity-entropy 3D thermodynamic surface of the adsorbed CO2 was obtained by the Gibbs’ thermodynamic graphical method. The thermodynamic surface established in this work will contribute and/or accelerate the research of the actual adsorption thermodynamic cycle and new findings are encouraged to be updated to our database to enhance the development on thermodynamic characteristics of the adsorption technology.

Introducing purifiers into hydrogen network can enhance the recovery and reuse of hydrogen in refineries, further reducing the consumption of fresh hydrogen. Based on previous graphical methods, this work proposes a simple and unified graphical method for integration of hydrogen networks with purification processes. Scenarios with different hydrogen concentrations of purified product can be analyzed by the unified procedure. As a result, the maximum hydrogen saved by purification reuse can be identified and the corresponding purification process can be optimized. The proposed method is easy and non-iterative, and it is valid to purification processes with any feed concentration. A conventional hydrogen network is analyzed to test the effectiveness of the proposed method.

In this work, a graphical method is developed for optimizing the purification recovery and feed simultaneously. Based on the hydrogen network integration, the effect of the hydrogen recovery on the fresh hydrogen consumption and the pinch location is analyzed systematically. The fresh hydrogen savings (or Hydrogen Utility Savings, HUS) versus R diagram is constructed to identify the variation trend of the HUS and pinch along hydrogen recovery, as well as the limiting hydrogen recovery, optimal hydrogen recovery and the optimal HUS. Furthermore, the interaction between the purification feed purity (PFP) and hydrogen recovery is studied, the variation trend of the optimal PFP, limiting PFP and the corresponding HUS along the hydrogen recovery are plotted in the same quantitative diagram. The PFP and hydrogen recovery are optimized simultaneously, together with the minimum fresh hydrogen consumption and pinch determined. The case study shows that the proposed method can identify the optimal hydrogen recovery, optimal purification feed purity, optimal HUS and the pinch accurately and conveniently.

A graphical method is developed for evaluating the thermodynamic feasibility of combined absorption vapor compression (AVC) and low-temperature multi-effect evaporation (LT-MEE) desalination systems. The method is based on the diagram showing the relationship among the vapor pressure, temperature and concentration of absorbent solution and seawater. Three commonly used absorbent solutions—LiBr-H2O, LiCl-H2O and CaCl2-H2O, are taken as examples. A five-step procedure is proposed and three systems—a conventional water-only system, a water-refrigeration cogeneration system and an intermediate vapor absorption water-only system, are analyzed for illustration purpose. Requiring only a small amount of information, the method is suitable to be used in the preliminary planning or design phase of an AVC-MEE system. Besides, the method can also give the values or ranges of several important parameters for the AVC-MEE systems being evaluated to be feasible, thus providing useful information for further investigation.

Energy integration is a key solution in chemical process and crude refining industries to minimise external fuel consumption and to face the impact of growing energy crises. Typical energy integration projects can reach a reduction of heating fuels and cold utilities by up to 40% compared with original designs or existing installations. Pinch Analysis is a leading tool and regarded as an efficient method to increase energy efficiency and minimise fuel flow consumptions. It is valid for both natures of design, grassroots and retrofit situations. It can practically be applied to synthesise a HEN (heat exchanger network) or modify an existing preheat train for minimum energy consumption. Heat recovery systems or HENs are networks for exchanging heat between hot and cold process sources. All heat transferred from hot process sources into cold process sinks represent the scope for energy integration. On the other hand, energies required beyond this integrated amount are to be satisfied by external utilities. Graphical representations of Pinch Analysis, such as Composite and Grand Composite Curves are very useful for grassroots designs. Nevertheless, in retrofit situation the analysis is not adequate and besides it is graphically tedious to represent existing exchangers on such graphs. This research proposes a new graphical method for the analysis of heat recovery systems, applicable to HEN retrofit. 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 HENs. For a given network, 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. The application of the new graphical method to a case study showed savings of approximately 17% in energy demands and fuel consumption.

The residence time of the hydrogen consuming reactor affects its hydrogen consumption and the hydrogen network integration. Based on the integration of the hydrogen network, the quantitative relationship between the hydrogen consumption and the residence time is derived. The hydrogen utility adjustment versus residence time diagram is constructed to identify the variation trend line. Based on this, the minimum hydrogen utility adjustment and the location of pinch can be easily identified for any given residence time, and the sulfur content of the feed oil can be analyzed and optimized simultaneously. The hydrogen network of a refinery is analyzed, and the optimal residence time of the vacuum gas oil reactor is identified to be 0.813 h.

Hazard reduction and elimination play a major role in designing a user-friendly plant in order to prevent accidents. To achieve this, safety evaluation on the properties of the chemicals and the process during the early design stage (also known as inherent safety assessment) is important to understand the hazards posed by the process involved. Different approaches have been proposed for inherent safety assessment methods, e.g. the index-based, simple graphical and computer aided methods. These methods evaluates different alternatives of process routes through scores assignment and rank them accordingly from the safest to the most hazardous process route. This paper proposes a Graphical Descriptive Technique for Inherent Safety Assessment (GRAND) for inherent safety evaluation during the research and development (R&D) stage of process design. GRAND is extended to 2-Dimensional Graphical Rating (2DGR) technique and may serve twofold purposes, (1) highlight chemical and process properties that contribute significantly to the maximum hazards through visualization (2) grouped the process routes evaluated three coloured regions which are red, yellow and green indicating the most hazardous, hazardous and the least hazardous levels respectively. Methyl methacrylate (MMA) manufacturing routes were chosen as a case study to illustrate the usage of the root-cause analysis as well as the 2DGR. The root-cause analysis of MMA manufacturing routes shows that GRAND Total Score of C2/PA based route is affected the most by hydrogen and formaldehyde. The 2DGR shows that ACH based route is assigned in the red region indicating it as the most hazardous route while i-C4 and TBA based route are assigned in the green region indicating them as the least hazardous routes in MMA manufacturing process.

A change in the system Gibbs free energy can be used as a criterion for spontaneous reactions, including the ferroelectric domain switching process. In this work, a new effective graphical method is introduced to investigate the change in the Gibbs free energy of a grain system and intuitively represent the domain switching state since its expression is too complex to study directly. A barium titanate crystal is considered as an example, and only 90∘ domain switching is involved. We can obtain two kinds of applications by virtue of the graphical method by controlling different variables in the change of the free energy: one application involves a new form of a ferroelectric domain switching criterion that considers the effect of the grain size, and the other application involves the critical single-domain grain size. For different loading methods, there will be different critical single-domain grain sizes in ferroelectrics.

Introducing purification devices into hydrogen systems can enhance the extent of hydrogen reuse. However, the economic performance of a purification device depends on its appropriate placement within a hydrogen system. Based on some established graphical methods, this paper explores the influences of the feed concentration on the purification proces s . A simple and systematic graphical method is proposed for identifying the OPP (optimal purification process) by extending the well-known pinch technology method. The proposed method can determine the OPP with the minimum feed flow rate and minimum tail gas flow rate under the condition of maximizing the HUS (hydrogen utility savings). The corresponding feed streams of the OPP also can be identified easily in the purification polygon. Furthermore, the conception of minimum separation work is used to compare different purification processes. A realistic case study is used to illustrate the applicability of the proposed method. Three different scenarios are analyzed and the results show that notable reductions in the minimum separation work consumption can be achieved (22%, 34% and 16% for the three scenarios).