The scientific paper proposes a pragmatic perspective of presenting some theoretical and practical aspects regarding a new approach within the studied organization, a process-based approach. The ...point of view submitted is a small part of the possibilities to implement the process-based approach. For an overview, I did a presentation of the organization in which I carry out my activity, the Sibiu County Directorate for the Registration of Persons, I showed the place and the role of the organization. Later, I explained the way, was organized and the activities that take place in the organization. An important aspect was the realization, in the organization, of personal analysis to make a new, process-based approach. Based on these processes we have made a current map of processes. A further direction of research is building a new process map following analysis to improve the processes within the studied public organization. Subsequently, we intend to execute the modeling of processes with a method that we will establish later.
In the present study, laser cladding of Inconel 718/TiC metal matrix composite coating on SS 304 was carried out using a 2 kW Yb-Fiber laser by preplaced and blown powder method. The molten pool ...thermal history during the deposition process was monitored using an IR pyrometer and correlated with the evolution of microstructure. The effect of various process parameters, viz. laser power ‘P’ (400 W – 1200 W), scanning speed ‘V’ (200 mm/min to 1400 mm/min) and powder feeding rate (8 g/min – 20 g/min) on the molten pool lifetime and cooling rate is investigated. Molten pool lifetime increased and cooling rate decreased with the decrease of scanning speed and increase of laser power. However, scanning speed had dominant effect on the molten pool lifetime and cooling rate compared to laser power. Moderate molten pool lifetime resulted in the formation of shell-core structure between Inconel 718 matrix and TiC particles. The longer molten pool lifetime (>0.45 s) resulted in complete decomposition of TiC particles rendering brittleness to the coating. The feasibility of detecting TiC particle decomposition in Inconel 718 matrix from the recorded thermal cycles based on multiple solidification shelfs is discussed. At the end, a process map based on a combined process parameter, PD/V2 (spot diameter D) and molten pool lifetime (τ) was developed. An optimum range of molten pool lifetime i.e. 0.25 s < τ ≤ 0.45 s was found to result in a good quality of coating with the formation of shell-core structure both in case of preplaced and blown powder laser cladding method.
•Laser cladding of Inconel 718/TiC MMC coating is carried out.•Influence of process parameters on molten pool thermal history is reported.•Decomposition of ceramic particles is correlated with molten pool lifetime.•Process map based on the molten pool lifetime is developed.•Reproducibility and repeatability of results with respect to molten pool lifetime is reported.
We propose a simple method to construct a process map for additive manufacturing using a support vector machine. By observing the surface of the built parts and classifying them into two classes ...(good or bad), this method enables a process map to be constructed in order to predict a process condition that is effective at fabricating a part with low pore density. This proposed method is demonstrated in a biomedical CoCr alloy system. We show that the proposed method is effective at reducing the number of experiments necessary to tailor an optimized process condition. This study also shows that the value of a decision function in a support vector machine has a physical meaning (at least in the proposed method) and is a semi-quantitative guideline for porosity density of parts fabricated by additive manufacturing.
IN738LC is an important high performance Ni-based superalloy. Its additive manufacturing via selective laser melting (SLM), however, is rather challenging due to the cracking-prone nature of the ...alloy whose chemical composition contains high amount of alloying elements namely Ti and Al. We address this significant problem by this study through systematic investigations on the pre-processing, SLM optimization, and post-processing of the material, as well as using advanced analytical tools such as micro-CT. A comprehensive process map for achieving crack-free, high-density samples (∼99.76%) is provided. Mechanisms influencing densification, cracking and mechanical properties are discussed. Excellent mechanical properties have been achieved at both room temperature (895/1010 MPa as the yield and tensile strengths) and elevated temperature of 850 °C (720 MPa tensile strength and 14.4% elongation). A demonstrative as-printed turbine blade is also presented, highlighting the capability of SLM to simultaneously achieve excellent mechanical property and good geometric integrity.
•Selective laser melted IN738LC superalloy shows high density (∼99.76%).•SLM process map provided for the IN738LC superalloy.•Good mechanical property (720 MPa and 14.4% elongation) achieved at 850 °C.•Defects mitigation approaches provided, followed by mechanism discussion.
In this study, a process map was developed in an effort to improve the understanding of dry granulation of pharmaceutical excipients by roll compaction process, and to implement the quality-by-design ...(QbD) approach. Through development of the process map, a correlation was made between the critical process parameters (roll pressure, screw speed), and critical quality attributes (density of ribbons and granule size). This method reduces development time, quantity of materials required and cost. A new excipient formulation based on natural polymers (lignin and cellulose) was utilised to improve the properties and reduce costs associated with tablets production. A variety of lignin, microcrystalline cellulose (MCC) and lactose monohydrate formulations were compacted followed by milling to obtain granules. Formulations were also characterised in terms of compressibility and flowability. Density of ribbons as well as granule size distribution were mapped versus critical process parameters. Based on this work as initial study, roll pressure was found to be a critical process parameter, higher ribbon density and larger granule size obtained with higher roll pressure. It was also revealed that the process map is a powerful tool in understanding the dry granulation, and can be used to construct a design space for pharmaceutical manufacturing.
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•Application of continuous dry granulation in production of pharmaceutical granules•Development of process map for dry granulation using roller compactor•Application of natural polymer (lignin) to improve the granulation of materials
Characterizing melt pool shape and geometry is essential in Metal Additive Manufacturing (MAM) to control the printing process, and avoid defects. Predicting melt pool flaws based on process ...parameters and powder material is difficult due to the complex nature of MAM processes. Machine learning (ML) techniques can be useful in connecting process parameters to the type of flaws in the melt pool. In this work, we introduced a comprehensive framework for benchmarking ML for melt pool characterization. An extensive experimental dataset has been collected from more than 80 MAM articles containing MAM processing conditions, materials, melt pool dimensions, melt pool modes and flaw types. We introduced physics-aware MAM featurization, versatile ML models, and evaluation metrics to create a comprehensive learning framework for melt pool defect and geometry prediction. This benchmark can serve as a basis for melt pool control and process optimization. In addition, data-driven explicit models have been identified to estimate melt pool geometry from process parameters and material properties. These models have been shown to outperform Rosenthal estimation for melt pool geometry while maintaining interpretability.
•Laser surface remelting of Inconel 718 is carried out.•Correlation between scan speed, cooling rate and microstructure is reported.•Process map based on cooling rate to generate preferred ...microstructure is developed.•Higher cooling rates resulted in decreased elemental segregation in Inconel 718.•Higher cooling rates resulted in improved performance of remelted samples.
In the area of laser material processing, laser surface remelting has been found to be an effective method of improving surface properties such as hardness, wear, and corrosion resistance. However, the scale of improvement depends on the evolving microstructure and phases, which depend on the cooling rates. Therefore, in the present study, laser surface remelting of Inconel 718 was carried out and a process-structure–property relationship with respect to the cooling rates has been developed. During the laser surface remelting process, the molten pool thermal history i.e. cooling rate, molten pool lifetime, and solidification shelf time is monitored and estimated using an IR pyrometer. The evolution of microstructure is later correlated with these parameters. With an increase in scan speed, the cooling rate is found to increase resulting in transformation of microstructure from equiaxed grains to columnar epitaxial growth. Based on the results obtained, a process map is proposed to establish a particular type of microstructure with respect to the cooling rate. Further, the effect of cooling rate and microstructure on the surface hardness and specific wear rate has also been investigated. Both surface hardness and specific wear rate got reduced with decreasing cooling rate at a slower scan speed due to grain coarsening and an increase in elemental segregation or Laves phase formation.
Clinical genomics demands close interaction of physicians, laboratory scientists, and genetic professionals. Taking genomics to scale requires an understanding of the underlying processes from the ...perspective of nongenetic physicians who are new to the field. We identified components of the processes amenable to adaptation when scaling up clinical genomics.
Semistructured interviews informed by the Theoretical Domains Framework with nongenetic physicians, who were using clinical genomics in practice, were guided by an annotated process map with 7 steps following the patient’s journey. Findings from the individual maps were synthesized into an overview process map and a series of individual maps by common location and specialty. Interviews were analyzed using the Theoretical Domains Framework.
In total, 16 nongenetic physicians (eg, nephrologists, immunologists) participated, generating 1 overview and 10 individual process maps. Sixteen common steps were identified across clinical specialties and locations, with variations over 9 steps. We report the potential for standardization across these 9 steps.
When scaling up complex interventions, it is essential to identify steps where variation can be accommodated. With these results we show how process mapping can be used to identify steps where variation is acceptable during scale up to accommodate adaptation to local context, allowing for the inevitable evolution of factors influencing ongoing implementation and sustainability.
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Understanding students' learning characteristics is central to successfully designing student-centered learning. Particularly in the problem-solving area, it is vital to know that students can ...possess their styles to solve problems, which should be considered central to addressing adaptive learning. To date, analyzing students' learning characteristics has been mainly based on their final answers. However, there is a limit to understanding the thinking process of students with the correct answer, because their responses are,
, singular and identical. With this background, we propose an approach for investigating students' cognitive behavior in problem-solving using response time in the process data. In this paper, we analyzed an item in Programme for International Student Assessment 2012 Creative Problem Solving (CP038q1). We analyzed log data from the PISA CPS item
encompassing 30,453 students (7,196 students with the correct answer and 23,257 students with incorrect answers) from 42 countries. We found that students with the correct answer are categorized into four clusters, and the problem-solving patterns of each cluster are distinguishable. We also showed the internal validity of this approach by confirming that students with incorrect answers can also be similarly classified. Our results indicate that allotted response time in an item can shed light on several distinguished problem-solving patterns, which implies that adaptive learning and feedback are vital for them.
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