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The purpose of this paper is to study the functionality of additively manufactured (AM) parts, mainly depending on their dimensional accuracy and surface finish. However, the products manufactured using AM usually suffer from defects like roughness or uneven surfaces. This paper discusses the various surface quality improvement techniques, including how to reduce surface defects, surface roughness and dimensional accuracy of AM parts.

There are many different types of popular AM methods. Unfortunately, these AM methods are susceptible to different kinds of surface defects in the product. As a result, pre- and postprocessing efforts and control of various AM process parameters are needed to improve the surface quality and reduce surface roughness.

In this paper, the various surface quality improvement methods are categorized based on the type of materials, working principles of AM and types of finishing processes. They have been divided into chemical, thermal, mechanical and hybrid-based categories.

The review has evaluated the possibility of various surface finishing methods for enhancing the surface quality of AM parts. It has also discussed the research perspective of these methods for surface finishing of AM parts at micro- to nanolevel surface roughness and better dimensional accuracy.

This paper represents a comprehensive review of surface quality improvement methods for both metals and polymer-based AM parts.

Reviews the inherent advantages, i.e. design flexibility and processing, of manufacturing piezoelectric ceramics and composites with numerous architectures via rapid prototyping techniques. Reports on processing in which piezoelectric ceramics and composites with novel and conventional designs were fabricated using rapid prototyping techniques. Fused deposition of ceramics, fused deposition modeling, and Sanders prototyping techniques were used to fabricate lead‐zirconate‐titanate ceramics and ceramic/polymer composites via, first, direct fabrication and, second, indirect fabrication using either lost mold or soft tooling techniques.

The usage of additive manufacturing (AM) technology in industries has reached up to 50 per cent as prototype or end-product. However, for AM products to be directly used as final products, AM product should be produced through advanced quality control process, which has a capability to be able to prove and reach their desire repeatability, reproducibility, reliability and preciseness. Therefore, there is a need to review quality-related research in terms of AM technology and guide AM industry in the future direction of AM development.

This paper overviews research progress regarding the QC in AM technology. The focus of the study is on manufacturing quality issues and needs that are to be developed and optimized, and further suggests ideas and directions toward the quality improvement for future AM technology. This paper is organized as follows. Section 2 starts by conducting a comprehensive review of the literature studies on progress of quality control, issues and challenges regarding quality improvement in seven different AM techniques. Next, Section 3 provides classification of the research findings, and lastly, Section 4 discusses the challenges and future trends.

This paper presents a review on quality control in seven different techniques in AM technology and provides detailed discussions in each quality process stage. Most of the AM techniques have a trend using in-situ sensors and cameras to acquire process data for real-time monitoring and quality analysis. Procedures such as extrusion-based processes (EBP) have further advanced in data analytics and predictive algorithms-based research regarding mechanical properties and optimal printing parameters. Moreover, compared to others, the material jetting progresses technique has advanced in a system integrated with closed-feedback loop, machine vision and image processing to minimize quality issues during printing process.

This paper is limited to reviewing of only seven techniques of AM technology, which includes photopolymer vat processes, material jetting processes, binder jetting processes, extrusion-based processes, powder bed fusion processes, directed energy deposition processes and sheet lamination processes. This paper would impact on the improvement of quality control in AM industries such as industrial, automotive, medical, aerospace and military production.

Additive manufacturing technology, in terms of quality control has yet to be reviewed.

This review paper aims to provide an overview of applications of direct rapid manufacturing assisted mold with conformal cooling channels (CCCs) and shows the potential of this technique in different manufacturing processes.

Key publications from the past two decades have been reviewed.

This study concludes that direct rapid manufacturing technique plays a dominant role in the manufacturing of mold with complicated CCC structure which helps to improve the quality of final part and productivity. The outcome based on literature review and case study strongly suggested that in the near future direct rapid manufacturing method might become standard procedure in various manufacturing processes for fabrication of complex CCCs in the mold.

Advanced techniques such as computer-aided design, computer-aided engineering simulation and direct rapid manufacturing made it possible to easily fabricate the effective CCC in the mold in various manufacturing processes.

This paper is beneficial to study the direct rapid manufacturing technique for development of the mold with CCC and its applications in different manufacturing processes.

This paper focuses on organizational change through the business process management approach. While “business process modeling” permits understanding process activities and their activities with other participants, “current reality tree (CRT)” technique promotes the identification of process constraints. The purpose of this study is to compare the results from applying both diagnostic techniques, process modeling, using the business process modeling notation, and root cause analysis, using the CRT.

The comparison is made using a pre-experiment in which two teams conducted diagnoses concomitantly in the information technology management (ITM) process of one unit of the biggest and prestigious higher education institution (HEI) in Brazil.

The modeling technique and the CRT should be considered complementary techniques, since applying one does not diminish or exclude the importance of using the other. Results were compared analyzing which dimensions of the process each technique highlighted: strategy, organization, activity/information and resources.

A possible limitation of this research is that the experiment was conducted in a single process and the result cannot be generalized to other processes.

It may be noted that the main contribution of this study is the presentation of the steps of two techniques for process diagnosis. It is expected that with the reports on diagnoses outcomes, team's assessment and the perception of the managers presented here other improvement teams may use the results of this research as an inspiration to perform process diagnosis, and as basis for decision making to define which technique to use according to the specific needs of process improvement.

The paper stands out the comparison of the technique application's outcomes. This study offers valuable insights to the organizations that are interested in restructuring their processes. It delineates many important benefits of such a diagnosis techniques. It also identifies possible pitfalls and recommends guidelines for the successful conduction of process diagnoses initiatives.

The purpose of this study is to benchmark the use of process improvement techniques among US health care organizations that won the Malcolm Baldrige National Quality Award.

The applications from 13 Baldrige award winning health care organizations were researched to determine which process improvement techniques were used most frequently to guide their operations.

The results from this study identify several best practices in process improvement techniques. Furthermore, the study pinpoints in which aspect of performance that a process improvement technique is most likely to be used.

Only applications from organizations winning the Baldrige award have been studied. The identity and application for organizations that do not win the award are not released to the public. Statistical analysis of the data is limited to the relatively small number (13) of award winners.

The results clearly show that there are certain process improvement techniques used by a majority of the Baldrige winners. It is not possible to guarantee that the use of these same techniques by other health care organizations will result in performance improvement, only that the winners used the techniques and have achieved a high level of performance. The results identify processes for further benchmarking studies.

The process improvement techniques identified in this study have been used by successful health care organizations. This information may be useful to other health care organizations when deciding on which process improvement techniques to pursue in order to improve their own performance. While the Baldrige award process has driven benchmarking efforts, this study uses the Baldrige process to identify benchmarking opportunities for process improvement in health care organizations.

Using 12 case studies, the purpose of this paper is to investigate the use of business analysis techniques in BPR. Some techniques are used more than others depending on the fit between the technique and the problem. Other techniques are preferred due to their versatility, easy to use, and flexibility. Some are difficult to use requiring skills that analysts do not possess. Problem analysis, and business process analysis and activity elimination techniques are preferred for process improvement projects, and technology analysis for technology problems. Root cause analysis (RCA) and activity-based costing (ABC) are seldom used. RCA requires specific skills and ABC is only applicable for discrete business activities.

This is an exploratory case study analysis. The author analyzed 12 existing business reengineering (BR) case studies from the MIS literature. Cases include, but not limited to IBM Credit Union, Chase Manhattan Bank, Honeywell Corporation, and Cigna.

The author identified eight business analysis techniques used in business process reengineering. The author found that some techniques are preferred over others. Some possible reasons are related to the fit between the analysis technique and the problem situation, the ease of use-of-use of the chosen technique, and the versatility of the technique. Some BR projects require the use of several techniques, while others require just one. It appears that the problem complexity is correlated with the number of techniques required or used.

Small sample sizes are often subject to criticism about replication and generalizability of results. However, this research is a good starting point for expanding the sample to allow more generalizable results. Future research may investigate the deeper connections between reengineering and analysis techniques and the risks of using various techniques to diagnose problems in multiple dimensions. An investigation of fit between problems and techniques could be explored.

The author have a better idea which techniques are used more, which are more versatile, and which are difficult to use and why. Practitioners and academicians have a better understanding of the fit between technique and problem and how best to align them. It guides the selection of choosing a technique, and exposes potential problems. For example RCA requires knowledge of fishbone diagram construction and interpreting results. Unfamiliarity with the technique results in disaster and increases project risk. Understanding the issues helps to reduce project risk and increase project success, benefiting project teams, practitioners, and organizations.

Many aspects of BR have been studied but the contribution of this research is to investigate relationships between business analysis techniques and business areas, referred to as BR dimensions. The author try to find answers to the following questions: first, are business analysis techniques used for BR project, and is there evidence that BR affects one or more areas of the business? Second, are BR projects limited to a single dimension? Third, are some techniques better suited for diagnosing problems in specific dimensions and are some techniques more difficult to use than others, if so why?; are some techniques used more than others, if so why?

The purpose of this study is to develop a map for the holistic business process management (BPM) diagnosis in order to guide the choice of techniques that encompass all dimensions of the business process.

The design science research method was used, with the elaboration of seven steps to project solutions to empirical problems: (1) identification of the problem, (2) awareness of the problem, (3) definition of expected results, (4) design and development, (5) demonstration, (6) evaluation of artifacts and (7) communication. These steps were organized in different analyzes: descriptive, experimental and observational. The descriptive analysis comprised steps one to three (identification of the problem, awareness of the problem, definition of expected results) and made use of the systematic literature review procedure for proposing artifacts. The experimental analysis comprised steps four to five (design and development, and demonstration), where the consultation with specialists' procedures and then the Delphi procedure for the construction of the artifacts were carried out. In the observational analysis, steps six (evaluation of artifacts), where two case studies were performed, and step seven (communication), in which the map for the holistic BPM diagnosis was presented were carried out.

The article systematizes the BPM diagnostic techniques scattered throughout the literature and relates how these techniques relate to dimensions. A map for the holistic BPM diagnosis is generated containing 21 techniques and 9 dimensions, with 45 relationships between these techniques and tools. Another aspect is that the map shows that in BPM promotion projects, techniques are not restricted to any specific phase of the life cycle.

Professionals can use the map to form a blend with selected techniques and use them for holistic BPM diagnosis according to the skills and other resources of the project team.

The map developed is innovative because it relates a set of consolidated techniques for each dimension of the process to provide the holistic diagnosis for the organization. It is important to highlight that these techniques and dimensions were scattered in the literature.

The paper discusses the problem of business process modelling, various techniques which are used to carry out business process modelling and aims to analyse the use of different techniques to find a better solution.

Business process modelling techniques could be divided into two groups, the diagrammatic and tabular techniques. As a representative of diagrammatic techniques, a flowchart is chosen and discussed in detail. A process model could also be developed using the activity table as a representative of tabular techniques. A comparative analysis of the two techniques is consequently carried out. The pros and cons of both techniques were analysed on the two case‐studies – the problems of Sales_Claim and Credit_Card are used as examples to test both techniques.

Based on the comparative analysis, several useful remarks are given as a result of this work. First, both techniques are simple and useful for business processes modelling. Drawing a flowchart is easier than developing an activity table. Second, it was found that the flowchart technique is too flexible and does not possess any mechanism to control gaps which could exist in the process model. On the other hand, the vertical linkage mechanism imposes a strict order on the development of the activity table, which enable the analyst to discover gaps existing in the table. Third, it was found that the visibility of a flowchart is good when the model is relatively small, but it becomes unclear in large models. The activity table is more visible even when the table contains hundreds of activities. The visibility depends on the analyst and his/her experience; many analysts prefer a diagrammatic presentation of processes, whereas other analysts are more tabular‐oriented. Fourth, concerning user involvement, the structure of the activity table requires an active user involvement, because every user (internal entity) occupies a certain column in the table, where the entity's activities are indicated. For this reason, the user is interested in cooperating in defining his/her activities correctly. On the other hand, the user's role in creating a flowchart does not go beyond observation. Business process modelling is a complex and difficult task. Using one technique may result in a model that does not reflect the original business process. For this reason, using a combination of both techniques could produce a process model which represents a true reflection of reality. Thus, it is suggested that because of the strict role imposed by vertical linkage, the analyst starts process modelling by developing the activity table and then continues by transforming the table into a flowchart. Having such a flowchart, which represents a good transformation of the original business process, is essential for successful continuation of business process simulation or other methods for business process improvement or reengineering.

The paper summarises and suggests several useful remarks as a result of this work, which also recommends the possibility of linking the two techniques to develop better business process models.

A systems perspective of waste management allows an integrated approach not only to the five basic functional elements of waste management itself (generation, reduction, collection, recycling, disposal), but to the problems arising at the interfaces with the management of energy, nature conservation, environmental protection, economic factors like unemployment and productivity, etc. This monograph separately describes present practices and the problems to be solved in each of the functional areas of waste management and at the important interfaces. Strategies for more efficient control are then proposed from a systems perspective. Systematic and objective means of solving problems become possible leading to optimal management and a positive contribution to economic development, not least through resource conservation. India is the particular context within which waste generation and management are discussed. In considering waste disposal techniques, special attention is given to sewage and radioactive wastes.