Preliminary Modeling Research Articles

Increase Effectiveness of Shaving by Using Wear-Resistant Coatings and Preliminary Modeling Cutting

Study of influence the edge and surface preparation and use of various types of coatings on the shaving cutters from the high-speed steel DIN 1.3243 (W6Mo5Cr4V2Co5 - China), with a hardness of 62-64HRc, for processing of the driven gear part, made of steel DIN 1.6523 (20CrNiMoH - China) with a hardness of 156-207 HB is presented. For the analysis, coatings based on titanium nitride (TiN) and a multicomponent coating of titanium and aluminum (AlTiN) were used. The coating on the basis of titanium nitride (TiN) increased the tool life 1.4 times. Multicomponent coating of titanium and aluminum (AlTiN) increased the tool life 1.6 times (AlTiN).

A preliminary analysis modeling of the relationship between quality management practices and sustainable performance

From the past literature, the relationship between quality practices and sustainable performance has not adequately been explored. Hence, this research attempted to further investigate the impacts of other variables that may proffer better explanation to the nature of the relationship. Therefore, the aim of this study is to examine the mediating and moderating effect of organizational excellence and environmental regulation and policy (ERP) on the relationship between TQM (quality practices) and sustainable performance by proposing an inclusive research model comprising the antecedent factors in food and beverage industry of Malaysia. Questionnaires were distributed to 303 Malaysian food and beverages companies while 168 questionnaires were returned (response rate above 50%) and PLS-SEM was used to analyze the data in order to assess the validity and reliability of the instrument. This study serves as a validation process for the developed instruments of the research with the identified constructs of the study while the preliminary analysis and results are shown. Also, the result reveals that the instruments are reliable and the analysis indicates a strong evidence of rational validity. Similarly, it reaffirms the importance of excellence for any successful strategic implementation in enhancing sustainable performance through the implementation of quality practices.

Evaluation of optimal lateral resisting systems for tall buildings subject to horizontal loads

The tendency of modern designs towards optimal structures often leads to the lightest and best performing choice among a large set of design alternatives. In a similar scenario, the introduction of automated tools to further guide designers in achieving efficient solutions has been a recurrent topic for mechanical and structural engineers, over the past decades. Nowadays, topology optimization is considered a powerful preliminary design tool to determine the optimal material distribution in a design domain, i.e. the most effective configuration that satisfies a given set of prescribed constraints while reducing the consumption of structural material. Among different applications in the field of Civil Engineering, this work focuses on the definition of optimal layouts of lateral resisting systems for multi-storey steel building frameworks subject to lateral loads using topology optimization techniques. The objective of the research is to illustrate the benefits deriving from the introduction of automated routines within the preliminary design stage and establish reliable guidelines for performing accurate and objective optimization procedures. Since the optimal material distribution follows the load flow within the structure, optimal topologies are especially sensitive to the alteration of support and loading conditions: different loading scenarios naturally lead to distinct optimal layouts. In order to avoid the loss of objectivity and preserve the optimality of the results, the effects that preliminary modelling and loading assumptions produce on final layouts are investigated. Numerical applications to high-rise building models are presented and discussed.

Preliminary sediment modeling at the confluence of the Mahakam and Karang Mumus River

The sedimentation process can move slowly and continuously during sediment transportation is still ongoing from the mainland. The sediment evidence has been done by pairing the current bathymetric measurement of the previous data from the bathymetric map of the DISHIDROS of the Indonesian Navy 2011 in the confluence of the Mahakam and Karang Mumus River. Initially, the tidal measurements were carried out on 15-29 January 2019 while the bathymetry measurements were measured on 21-22 January 2019 during spring tide was over 800 m from upstream to downstream river confluences. Contour modeling measured using Software Surfer while the tidal is using the Admiralty method., to get discharge sediment performed contour coupling from both using AutoCAD software. The results of tidal analysis at the confluence of this river type Mixed Tide, Prevailing Semi Diurnal with MSL119 cm, HHWL 275 cm and LLWL-29 cm. Besides, the results of the sedimentation calculation showed an increase of 251,621.52 m3 in the tempo of 8 years from different Years of measurement. Most of the deposits occur on the opposite side of the Karang Mumus River, and this may be due to the small current velocity of the inner side of the Mahakam River that is curved towards the Karang Mumus River. Further research should also be modeled on current patterns and numerical modeling to ensure the morphological changes of the confluence of the present river.

Computer Simulation of a Group of Mobile Robots in Special Software Tools

The problem of controlling a group of special robots for application in the high-risk conditions (for example, for fire extinguishing, search for hazardous substances, or elimination of consequences of emergencies) is solved. According to the task, robots operate in the industrial and urban environment, i.e., the movement of robots is planar. Various strategies of group interaction between robots are analyzed; a literature review is conducted. Due to the task specifics, a decentralized management strategy has been selected. For solving the problem, a movement algorithm of a group of mobile robots with a subsequent visual check of the resulting algorithm operation is proposed. Implementation of the algorithm’s work is performed in the MATLAB environment. For preliminary algorithm verification and modeling of various dangerous cases, a model of robot group using the Mobile Robotics Simulation Toolbox of MATLAB was made. For a more detailed and accurate analysis of the real robot’s behavior, a model in the ROS package has been developed. That model interacts with the developed algorithm through the ROS Toolbox package of MATLAB. This software can be used for the training of engineering staff in the field of mathematical modeling, group control, and multi-agent systems. As a result of verification, the program and the model successfully solve the task. Yet, the model in the ROS package requires greater computational power because of the large number of complex calculations.

УМОЗРИТЕЛЬНОЕ МОДЕЛИРОВАНИЕ КАК МЕТОДОЛОГИЧЕСКИЙ ПРИЕМ ПО ВЫЯВЛЕНИЮ ПРИНЦИПОВ РЕПРЕЗЕНТАЦИИ МИРОВОЗЗРЕНЧЕСКИХ ИДЕЙ В ИЛЛЮМИНАЦИИ СРЕДНЕВЕКОВОЙ КАРТОГРАФИИ

Medieval cartography had a wide functionality. The world map served as a historiographical and didactic tool, a spiritual guide, a mnemonic matrix, a visual encyclopedia, a philosophical model, a means of meditative practices, a manuscript illustration, an exegetical and moralizing text, a method for transmitting of narrative information, ideological and pedagogical concepts. To process a vast layer of data contained in authoritative verbal sources, the rumination method was used by a medieval cartographer. And to create the map itself, it was necessary to carry out preliminary speculative modeling and solve the tasks of the artistic reproduction of the world model on a two-dimensional picture plane. An experiment in the humanities, including art history, is not a widespread method, but its application, in that case, can be effective. Taking into account the information contained in main verbal sources and following the path of the medieval cartographer, a speculative world model meeting the basic medieval worldview requirements was created in the article. Following the experiment, the basic representational principles of the image of the world were successfully identified, as well as the artistic techniques with which those principles could be applied on the visual plane were determined.

Preliminary Financial Modelling with Probabilistic Approach for Geothermal Development Project in Indonesia

The right of geothermal field concession in Indonesia is obtained by tender as per Law No. 21/2014 Article 18. In the submitted proposal, the developer candidates shall mention the plan of field development strategy, while available data is limited due to a preliminary survey or preliminary survey and exploration were just performed. Then the developer candidates must be able to formulate the financial condition of the project so that the field utilization not only sustains but also produces appropriate profits. This paper discussed some regulations which are related to the economics of geothermal development project in Indonesia and a simple example of financial modelling with a probabilistic approach using Microsoft Excel Monte Carlo simulation and analysis tool. The input data were some technical assumptions such as installed capacity, steam fraction, steam specific consumption (SSC), well’s capacity, well’s success ratio, and financial assumptions such as well’s price, power plant construction’s cost, operation and maintenance cost, and others. The output of modelling were NPV (Net Present Value), IRR (Internal Rate of Return) and parameters that were sensitive to both values, whether financially or technically. The result of simulation showed from the financial aspect, wells and power plant cost were the most sensitive parameters in IRR calculation, while well’s capacity and steam fraction were the most sensitive parameters from the technical aspect.

Preliminary modelling of forming forces in three directions for incremental sheet forming process based on the contact area

Incremental Sheet Forming (ISF) is a promising forming process for rapid prototype and small batch production of complex 3D shapes due to the enhanced flexibility, increased formability and the reduced forming force. However, the efficient prediction of forming forces in three directions is insufficient, which is critical to achieve the feed-back control and optimization of the process. In this paper, a new method to predict the forming force during the ISF process was proposed. First, the contact stress was obtained by analyzing the theoretical force condition of a unit body within the formed area. Then, the contact area between the forming tool and the sheet was modeled based on experimental examinations. In addition, a forming force prediction model for ISF especially in three directions was established according to actual contact condition and deformation mechanism. Meanwhile, experiments with different process parameters were carried out and a genetic algorithm was used to determine the essential coefficients of the theoretical model. Further, the prediction model of the forming force in three directions in ISF was obtained and the prediction accuracy was verified through extra experiments. The results confirmed that the force prediction has high accuracy and the maximum prediction error of the forming force is below 18%.

Digitalization of Legal Practices: New Opportunities

Fragmentary digital models of society and its legal life have already been created and used, including the ones used unconsciously and haphazardly. Improving the efficiency and reducing the level of budget, corporate and personal costs associated with the implementation of legal should be one of the goals of the "digital" legal policy. The authors investigate some applied aspects of developing digital models of law enforcement (in particular, the rules of forming the forecast of social and legal reality indicators). Successful digitalization of legal regulation, according to the authors, is impossible without building correct quantitative mathematical models using methods of both theoretical and empirical modeling. The article formulate recommendations for building stochastic models that allow to use the mathematical apparatus of the probability theory. It substantiates the expediency of using probabilistic values as quantitative indicators of such models. It identifiers the main directions of practical implementation of the proposed approaches. Such directions, in particular, include ensuring transition of rule-making practice from an intuitive assessment of the effectiveness of the projected legislation to a computational assessment based on preliminary mathematical modeling of the projected norms and their applications.

LED MODULE WITH ELECTRONIC ILLUMINATION CONTROL

Many energy saving tasks can be solved thanks to the current advances in LED technology in the production of semiconductor light sources. Modern production of solid-state LEDs guarantees high-precision compliance with the calculated design parameters of illumination devices. This opens up wide opportunities for high-precision control of the lighting parameters of a multicomponent module: light power, a directional pattern and a distribution of illumination. Today, the methodical issues of the preliminary modeling of LED illumination devices with the given parameters are fundamentally solved. There is a shift from manual calculations to computer design and need to develop and select the most effective mathematical modeling methods. The paper presents a consistent approach to the modeling of the distribution of illumination on a horizontal plane from the planar LED module, based on the Lambert type of radiation of a single point source. Simple mathematical expressions, programmed on a personal computer, are obtained. The example of a 25-LED floodlight has shown the ability of dynamic control the lighting characteristics of the module. Connecting patterns of separate LEDs or their groups allow to change the direction pattern of the lamp by the appropriate way of switching diodes with different aperture of radiation. The lighting power can be controlled within the linearity of the ampere-brightness characteristics by changing the current strength through the LED. The static selection of characteristics is controlled by the geometry of the location of discrete sources. The formation of uniform illumination of the plane is graphically illustrated. The electron-dynamic way of controlling the lighting parameters of the LED floodlight is confirmed by the inventor’s certificate.

Enabling multi-tier collaboration between supply chain dyads: a conceptual modelling framework

ABSTRACTRecent research argued that multi-tier collaboration is highly valuable in complex and uncertain supply chain environments. Yet, it is poorly investigated in literature and rarely implemented in the industry for trust and structure issues. To enable multi-tier collaboration, latest research suggests inducing collaboration between supply chain dyads instead of individual supply chain organisations. This article attempts to be the first footprint in this emerging research direction, suggesting an empirical modelling methodology for multi-dyad collaboration, as part of a larger study on collaboration between supply chain dyads. The objective is to provide a basic conceptual framework guiding the study of collaboration implementation through modelling. The proposed methodology is generic, simple and dynamic, meant to support a preliminary modelling analysis preceding a major real-setting implementation of multi-dyad collaboration. We expect that implementing the proposed framework will help supply chain managers gain a practical understanding of the extent to which a multi-dyad collaboration is feasible in their supply chain context.

METHOD FOR CONSTRUCTING THE MODEL OF COMPUTING PROCESSBASED ON PETRI NET

The aim of the work is to improve the quality of the computational process that solves the problem, due to its modeling and debugging based on the Petri net. The quality of the computational process is understood as the absence of errors (looping, paralysis, unreliability of some fragment, etc.) and its optimization according to the criterion of minimum complexity. The new approach to the analysis of the computational process, based on preliminary modeling by Petri nets of both fragments of computational processes and complete computational processes, is proposed. This will reveal many errors at the stage of modeling the computational process. The computational process is considered as a set of macrooperations, which are functionally, completed operations of various hierarchical levels. To locate macrooperations in a computational process, it is decomposed into elementary (basic) computational constructions. A statement that any computing process can be constructed on the basis of a relatively small number of macrooperations is formulated. To implement the new approach, the task of developing a method for constructing a Petri net according to a given computational process is formulated and solved. The essence of the proposed method consists in dividing the computational process into macrooperations, building a Petri net fragment for each macrooperation, modeling all fragments, assembling a complete Petri net from network fragments and modeling it. To implement the method, a procedure for constructing a computational process model is being developed. The stages of this procedure are described: decomposition of the computational process into macrooperations according to the proposed rules, translation of macrooperations into fragments of the Petri net and their modeling, collection of the complete Petri net by the proposed rules, and modeling the resulting Petri net. The results of the implementation of all stages of the procedure are recorded in the library, the aim of which is the accumulation of knowledge about the computational processes corresponding to them Petri nets and modeling results. This allows us to simplify the process of modeling a new computing process through the use of already debugged fragments. If the computational process contains errors or is not optimal, it is corrected, which allows to improve its quality according to the above criteria. By the example of sorting by inserts, the correctness of the operation of the constructed Petri net using the declared method is experimentally confirmed.

The December 22, 2018 Anak Krakatau, Indonesia, Landslide and Tsunami: Preliminary Modeling Results

On the evening of December 22, 2018, the coasts of the Sunda Strait, Indonesia, were hit by a tsunami generated by the collapse of a part of the Anak Krakatau volcano. Hundreds of people were killed, thousands were injured and displaced. This paper presents a preliminary modeling of the volcano flank collapse and the tsunami generated based on the results of a 2D depth-averaged coupled model involving a granular rheology and a Coulomb friction for the slide description and dispersive effects for the water flow part. With a reconstructed total volume (subaerial and submarine) of the landslide of 150 million $$\hbox {m}^{3}$$ inferred from pre and post-collapse satellite and aerial images, the comparison of the simulated water waves with the observations (tide gauges located all around the strait, photographs and field surveys) is satisfactory. Due to the lack of information for the submarine part of the landslide, the reconstructed submarine slope is assumed to be approximately constant. A significant time delay on the results and particularly in the Bandar Lampung Bay could be attributed to imprecisions of bathymetric data. The sensitivity to the basal friction and to dispersive effects is analyzed through numerical tests. Results show that the influence of the basal friction angle on the simulated wave heights decreases with distance and that a value of $$2^{\circ }$$ gives consistent results with the observations. The dispersive effects are assessed by comparing water waves simulated by a shallow water model and a Boussinesq model. Simulations with frequency dispersion produce longer wave periods and smaller wave amplitudes in the Sunda Strait and particularly in deep waters.

Preliminary long-term predictive modelling of groundwater resources in view of climate change – a case study from eastern Poland

The paper discusses an effective and simple approach to preliminary long-term predictive modelling to the estimation of the effects of predicted climate change on groundwater resources in aquifer recharged by rain infiltration for the end of the 21st century. The groundwater resources in an analysed catchment were assessed based on predicted precipitation and air temperature from seven climate change projections in two sets of the Intergovernmental Panel on Climate Change (IPCC) greenhouse gas emission scenarios (SRES), associated with various regional climate models (RCM). The predicted groundwater resources were obtained by diminishing the predicted renewable resources by recent environmental flows in a river dewatering the catchment. The predicted reserve was assessed taking into account the forecasted groundwater abstraction. The study revealed that the predicted groundwater reserve depended on the assumed prediction model, based on particular SRES and RCM ensembles. The groundwater resources in the study area at the close of the 21st century are expected to considerably decrease when compared to the reference period 1971–1990. The future groundwater reserve assessed by the climate change model based on IPCC emission scenario B2 connected with the regional climate model HIRHAM and regional climate model RCAO, may decrease when compared to the reference period, by 51 or 92%, respectively. In view of the IPCC emission scenario A2 assumptions, this preliminary predictive modelling shows that there may be a shortage of groundwater resources in the analysed catchment in the final decades of the 21st century.

Coal mine-affected water releases, turbidity and metal concentrations in the Fitzroy River Basin, Queensland, Australia

Historical water quality datasets from the Fitzroy Basin, a large river system that receives mine-affected water from more than 40 mines, and drains into the Great Barrier Reef Lagoon, were analysed. There is great public and environmental interest in these waters that are used for agriculture, recreation and raw drinking water supplies. Aside from one AMD-impacted area, waters were generally alkaline. Turbidity data regularly exceeded the regional water quality objective (< 50 NTU), indicating the presence of particulates that may accumulate or transport metal contaminants within the waters. Analyses of data for 14 metals showed dissolved Cu and Al, followed by Zn, were the parameters that were most often greater than Australian toxicant guideline values. Analysis of coal mine-affected water samples and the receiving creek data, showed that median turbidity was greater downstream than upstream of the mine water release points, suggesting release-water may contain particulate-bound metals. Median dissolved Al and Cu concentrations were lower downstream than upstream and were above guidelines. Preliminary modelling using WHAM7 suggested downstream dissolved Cu (2–5 µg/L) was bound to fulvic acid and was likely not bioavailable. Dissolved Al (170–550 µg/L) may have existed as Al(OH)4−. Overall, suspended particulate matter appeared to be a water quality parameter of interest in this mine-affected river basin. Further targeted sampling, direct measurement of particulate-bound metals and multivariate statistical analysis are needed to help better understand metal partitioning in these turbid, alkaline waters.

Comparative analysis of the parameters of the strength of the subgrade at the transition to the higher axial loading up to 25 t

A review of the scientific and technical literature on the re-alignment of the route during the transition to high axial load from the accepted today (23.5 t/axis) to the perspective (25 t/axis) shows that in the stage of preliminary researches imitation modeling of the earth web by the finite element method (ITU) as the most convenient, accurate and illustrative of the known numerical methods. In order to provide recommendations on the strength of the subgrade when moving to a higher axial load up to 25 t/axis, an analysis was conducted, the essence of which was to compare the stress-strain state of the subgrade at two loads per axis: 23.5 t/axis (existing ) and 25 (perspective). All the geometric and deformation characteristics of the formation are taken from data on a two-track section with a height of embankment of 3. The deformation characteristics are chosen so that the working material of the formation is in accordance with the average indices of deformation capacity of the railways used. The ITU train load calculus makes it possible to obtain all the factors of VAT in it, which is the main purpose of the study of the strength of the earth cloth, and allows to forecast their development in the future.

Methods of construction of objects taking into account the simulation of the temperature regime of hardening concrete

The article is devoted to the use of different methods of construction of the object, depending on the boundary conditions set in the process of its design and construction. The aim of this work is a compilation of the various methods of investigation of the temperature regime of hardening concrete, aimed at providing the required timing of the turnover of a formwork, with a view to ensuring the consumer properties of the structures. The scientific novelty of the work lies in the updating and testing of methods for regulating the heating of hardening concrete, ensuring the formation of the required consumer properties of structures not previously used in transport and civil construction, based on preliminary modeling of thermal processes occurring in the hardening concrete, through the calculation software. The use of modern calculation and analytical complex allowed to obtain the results as accurately as possible comparable with the observations obtained during construction, which allowed to develop projects for the production of works on concreting objects erected in different conditions, with the necessary consumer properties.

Preliminary Numerical Modeling of CO2 Geological Storage in the Huangcaoxia Gas Reservoir in the Eastern Sichuan Basin, China

Depleted gas reservoirs are important potential sites for CO2 geological sequestration due to their proven integrity and safety, well-known geological characteristics, and existing infrastructures and wells built for natural gas production. The Sichuan Basin has a large number of gas fields in which approximately 5.89×109 tons of CO2 can be stored. The Huangcaoxia gas field has the best opportunity in the eastern Sichuan Basin for a pilot project of CO2 sequestration due to its relatively large storage capacity and the nearly depleted state. A coupled thermal-hydrodynamic model including faults is built based on the geological and hydrogeological conditions in the Huangcaoxia gas field. The results of the numerical simulations show that the downhole temperature is above 80°C at a downhole pressure of 14 MPa under the constraint of temperature drop in the reservoir due to the strong Joule-Thomson effect. The corresponding injection pressure and temperature at the wellhead are 10.5 MPa and 60°C, respectively. The sizes of the pressure and CO2 plumes after an injection of 10 years are 18 km and 5 km, respectively. The zone affected by temperature change is very small, being about 1-2 km away from the injection well. The injection rate in the injection well Cao 31 averages 6.89 kg/s (21.73×104 tons/a). For a commercial-scale injection, another four wells (Cao 9, Cao 30, Cao 6, and Cao 22) can be combined with the Cao 31 well for injection, approaching an injection rate of 35 kg/s (1.10×106 tons/a). Both the pressure and temperature of CO2 injection decrease with the increasing depleted pressure in the gas reservoir when the latter is below 6 MPa. With the technique of CO2-enhanced gas recovery (CO2-EGR), the CO2 injection rate is improved and approximately 1.58×107 kg of gas can be produced during a studied time period of 10 years.

A Multitorch RF Plasma System as a Way to Improve Temperature Uniformity for High-Power Applications

This article presents a new approach and preliminary modeling results of the temperature field nonuniformity reduction by using a multitorch radio frequency (RF) plasma system. This is also a way to achieve technical and economic feasibility for plasma systems with plume power over 200 kW, significantly reducing the development and production cycle. The mixing of plasma jets was numerically simulated by solving a system of equations, describing high-temperature turbulent plasma flows. The data obtained could be used for engineering of high-power plasma systems, including the ones for testing high-temperature thermal protection materials, waste to power, syntheses of new materials, and so on.

Characteristic Fatigue Life Research on the Centrifugal Impeller

The researched work quite essentially deals with the resoluteness of the safety and structural integrity of the centrifugal impeller in withstanding the forces impacted on the targeted materials Ti-6Al-4V and Au2gn. In order to counteract the effects prevalent as a result of profound instabilities such as surging, stalling and choking, the materials were subjected to an intense comparative study, undertaken with respect to primary parameters such as good strength yield, in addition to dispensing a rotational speed of 20000 rpm. The preliminary solid modeling was executed using CATIAV5. Structural Analysis is carried out using ANSYS software in order to establish their strengths together with the location of maximum stress and strain. 2D FEM simulation was done on the impeller. Furthermore the number of cycles to failure was computed using the best amongst the known strain – based life estimation methods. From the modal analysis the ubiquitous critical mode shape along with the frequency at which the maximum relative displacement occurs were obtained. Finally, Ti-6Al-4V was affirmed to be better than Au2gn.