Processes

Editorial

Jump to: Research

3 pages, 181 KiB

Open AccessEditorial

Special Issue on Performance Measurement and Optimization for Sustainable Production Processes Improvement

by Changhee Kim

Processes 2020, 8(3), 287; https://doi.org/10.3390/pr8030287 - 3 Mar 2020

Cited by 1 | Viewed by 1874

Abstract

Sustainable production process improvement is very important for all enterprises as its implementation can help them to achieve development plans, scheduling, and reduce costs and pollution [...] Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

Research

Jump to: Editorial

24 pages, 3830 KiB

Open AccessArticle

Performance Evaluation Using Multivariate Non-Normal Process Capability

by Moath Alatefi, Shafiq Ahmad and Mohammed Alkahtani

Processes 2019, 7(11), 833; https://doi.org/10.3390/pr7110833 - 8 Nov 2019

Cited by 5 | Viewed by 7086

Abstract

Process capability indices (PCIs) have always been used to improve the quality of products and services. Traditional PCIs are based on the assumption that the data obtained from the quality characteristic (QC) under consideration are normally distributed. However, most data on manufacturing processes [...] Read more.

Process capability indices (PCIs) have always been used to improve the quality of products and services. Traditional PCIs are based on the assumption that the data obtained from the quality characteristic (QC) under consideration are normally distributed. However, most data on manufacturing processes violate this assumption. Furthermore, the products and services of the manufacturing industry usually have more than one QC; these QCs are functionally correlated and, thus, should be evaluated together to evaluate the overall quality of a product. This study investigates and extends the existing multivariate non-normal PCIs. First, a multivariate non-normal PCI model from the literature is modeled and validated. An algorithm to generate non-normal multivariate data with the desired correlations is also modeled. Then, this model is extended using two different approaches that depend on the well-known Box–Cox and Johnson transformations. The skewness reduction is further improved by applying heuristics algorithms. These two approaches outperform the investigated model from the literature because they can provide more precise results regardless of the skewness type. The comparison is made based on the generated data and a case study from the literature. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

25 pages, 16329 KiB

Open AccessArticle

Sustainable Design and Engineering: A Relationship Analysis between Digital Destructive and Non-Destructive Testing Process for Lightweight Concrete

by Muhammad Ahmed Qurashi, Syyed Adnan Raheel Shah, Muhammad Farhan, Muhammad Taufiq, Waleed Khalid, Hunain Arshad, Muhammad Tayyab, Gullnaz Shahzadi and Muhammad Waseem

Processes 2019, 7(11), 791; https://doi.org/10.3390/pr7110791 - 1 Nov 2019

Cited by 17 | Viewed by 3910

Abstract

The development of sustainable lightweight materials is a promising field solution in this era. The production of sustainable materials by replacing coarse aggregates with some lightweight alternative provides a good quality construction material. In this study, rocky coarse aggregates were replaced by an [...] Read more.

The development of sustainable lightweight materials is a promising field solution in this era. The production of sustainable materials by replacing coarse aggregates with some lightweight alternative provides a good quality construction material. In this study, rocky coarse aggregates were replaced by an ultra-lightweight material (i.e., expanded polystyrene beads) to produce an equivalent rock-solid mass of concrete. Using an M15 grade of concrete composition, expanded polystyrene (EPS) beads were added in place of aggregates in amounts ranging from 5% to 40% at a water–cement (w/c) ratio of 0.60. The specimen size as per American Society for Testing and Materials (ASTM) specification was 150 mm in diameter and 300 mm in length. Furthermore, statistical analysis for the relationship study for destructive testing (DT) (i.e., compressive test machine) and non-destructive testing (NDT) (i.e., rebound hammer and ultrasonic pulse velocity (UPV)) has been performed at developed specimens under 7- and 28-day curing conditions. In the end, the results showed that NDT predicts higher compressive strength than that of DT with the addition of EPS beads up to 20% aggregate replacement, after that it is vice versa for up to 40% aggregate replacement. This study will not only help in the production of sustainable lightweight materials, but especially concrete block production can also be performed at a large scale as a sustainable engineering solution. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

11 pages, 362 KiB

Open AccessFeature PaperArticle

Analysis of Inventory Turnover as a Performance Measure in Manufacturing Industry

by Jin Kyung Kwak

Processes 2019, 7(10), 760; https://doi.org/10.3390/pr7100760 - 17 Oct 2019

Cited by 20 | Viewed by 18209

Abstract

Using an appropriate measure to assess firms’ performance is essential. We analyzed inventory turnover (IT) as a performance measure in manufacturing processes because IT ratios are critical in the manufacturing industry and publicly available objective measures. Using the data of 421 manufacturing companies [...] Read more.

Using an appropriate measure to assess firms’ performance is essential. We analyzed inventory turnover (IT) as a performance measure in manufacturing processes because IT ratios are critical in the manufacturing industry and publicly available objective measures. Using the data of 421 manufacturing companies in Korea from 2010 to 2018, we conducted an extensive analysis of the factors affecting IT by segment and its correlation with other financial ratios. Then, we compare performances between the top and bottom companies determined by Altman’s Z score approach. We found that, for the overall manufacturing industry, IT ratios were negatively correlated with gross margin and debt cost, but positively correlated with capital intensity, although the results varied by segment. Moreover, IT ratios did not show significant correlations with other financial ratios categorized for growth, profitability, stability, productivity, and value of companies. However, adjusted IT (AIT) can be a good indicator of firms’ performance in terms of financial sustainability. Results also revealed that the top 10% companies showed higher AIT ratios than the bottom 10% in most segments of the manufacturing industry. The analysis of this study can be a starting point to search for a composite index to evaluate manufacturing processes comprehensively. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

22 pages, 7466 KiB

Open AccessArticle

Implementation of Production Process Standardization—A Case Study of a Publishing Company from the SMEs Sector

by Arturo Realyvásquez-Vargas, Francisco Javier Flor-Moltalvo, Julio Blanco-Fernández, Joanna Denisse Sandoval-Quintanilla, Emilio Jiménez-Macías and Jorge Luis García-Alcaraz

Processes 2019, 7(10), 646; https://doi.org/10.3390/pr7100646 - 21 Sep 2019

Cited by 23 | Viewed by 15344

Abstract

This paper reports a case study using a standardization process for increasing efficiency and a better optimization of resources in a printing company with 150 operators having manual and mechanical tasks in the box assembly department along with four production lines. The current [...] Read more.

This paper reports a case study using a standardization process for increasing efficiency and a better optimization of resources in a printing company with 150 operators having manual and mechanical tasks in the box assembly department along with four production lines. The current capacity is 350 boxes per day, while the demand is 650 units, where the company is expected to pay large sums for overtime. Using work standardization, studying worker movements, timing, and workstations redesign, the main goal was to increase the efficiency and productivity indexes. After applying those tools, the inefficient movements in operators decreased from 230 to 78, eliminating 66% of the unnecessary movements, as well as the standard time in a workstation decreased from 244 to 199 s (18.44%) per each assembled box, and the production rate increased by 63.2%, that is, 229 units per assembly line a day, where overtime was reduced to zero. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

16 pages, 1731 KiB

Open AccessFeature PaperArticle

What Is the Right Innovation Type for Your Industry? Evidence from Chemical Firms in Korea

by Jaeho Shin, Yeongjun Kim, Hongsuk Yang and Changhee Kim

Processes 2019, 7(10), 643; https://doi.org/10.3390/pr7100643 - 20 Sep 2019

Cited by 3 | Viewed by 4228

Abstract

The literature has two different perspectives on which innovation types should be implemented to achieve innovation performance; some argue that they should pursue process-oriented innovation, while others maintain that both product- and process-oriented innovation should be performed. Though innovation efficiency should be measured, [...] Read more.

The literature has two different perspectives on which innovation types should be implemented to achieve innovation performance; some argue that they should pursue process-oriented innovation, while others maintain that both product- and process-oriented innovation should be performed. Though innovation efficiency should be measured, which takes both input and output variables into account, the research so far has been measured only with the performance of the innovation. Accordingly, this study identifies which innovation type is the most advantageous in terms of innovation efficiency for the chemical firms. We use data of 64 Korean chemical companies from a 2016 Korean innovation survey and perform data envelopment analysis to calculate innovation efficiency. Kruskal–Wallis one-way ANOVA and bootstrap DEA were also conducted to compare the difference of innovation efficiency among groups, depending on which innovation types are oriented. The result shows that focusing on process innovation rather than both product and process innovation is more appropriate to achieve higher innovation efficiency, and pursuing process innovation rather than product innovation tends to achieve a higher level of innovation efficiency in the Korean chemical industry. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

18 pages, 2230 KiB

Open AccessArticle

Air-Core–Liquid-Ring (ACLR) Atomization Part II: Influence of Process Parameters on the Stability of Internal Liquid Film Thickness and Resulting Spray Droplet Sizes

by Marc O. Wittner, Miguel A. Ballesteros, Frederik J. Link, Heike P. Karbstein and Volker Gaukel

Processes 2019, 7(9), 616; https://doi.org/10.3390/pr7090616 - 10 Sep 2019

Cited by 10 | Viewed by 3868

Abstract

Air-core–liquid-ring (ACLR) atomization presents a specific type of internal mixing pneumatic atomization. It can be used for disintegration of high viscous feed liquids into small droplets at relatively low gas consumptions. However, the specific principle of ACLR atomization is still under research and [...] Read more.

Air-core–liquid-ring (ACLR) atomization presents a specific type of internal mixing pneumatic atomization. It can be used for disintegration of high viscous feed liquids into small droplets at relatively low gas consumptions. However, the specific principle of ACLR atomization is still under research and no guidelines for process and atomizer design are available. Regarding literature on pre-filming atomizers, it can be hypothesized for ACLR atomization that the liquid film thickness inside the exit orifice of the atomizer, as well as the resulting spray droplet sizes decrease with increasing air-to-liquid ratio (ALR) and decreasing feed viscosity. In this study, the time dependent liquid film thickness inside the exit orifice of the atomizer was predicted by means of computational fluid dynamics (CFD) analysis. Results were compared to high speed video images and correlated to measured spray droplet sizes. In conclusion, the hypothesis could be validated by simulation and experimental data, however, at high viscosity and low ALR, periodic gas core breakups were detected in optical measurements. These breakups could not be predicted in CFD simulations, as the simplification of an incompressible gas phase was applied in order to reduce computational costs and time. Nevertheless, the presented methods show good potential for improvement of atomizer geometry and process design as well as for further investigation of the ACLR atomization principle. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Graphical abstract

9 pages, 499 KiB

Open AccessArticle

Production Planning to Reduce Production Cost and Formaldehyde Emission in Furniture Production Process Using Medium-Density Fiberboard

by Taeho Kim

Processes 2019, 7(8), 529; https://doi.org/10.3390/pr7080529 - 9 Aug 2019

Cited by 6 | Viewed by 7171

Abstract

This research seeks to improve the production process in the Korean furniture industry by reducing the amount of medium-density fibreboard, that is commonly used to produce furniture, in order to reduce production costs and formaldehyde emissions. This research selects a representative company from [...] Read more.

This research seeks to improve the production process in the Korean furniture industry by reducing the amount of medium-density fibreboard, that is commonly used to produce furniture, in order to reduce production costs and formaldehyde emissions. This research selects a representative company from the Korean furniture industry to examine its optimal amount of medium-density fibreboard used, using the variables of a previous company; the sale levels, the Korea National Productivity Award Index, and technical efficiencies obtained from a previous study. By using its 2016 production level, we compare it with the amount of medium-density fibreboards actually used in 2016, and apply the results to the entire Korean furniture industry. In conclusion, the Korean furniture industry can minimize the amount of medium-density fibreboards used without reducing current production levels, and thereby save production costs, and contribute to substantially reducing formaldehyde emissions. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

23 pages, 1385 KiB

Open AccessArticle

How to Improve the Quality and Speed of Green New Product Development?

by Shi Yin, Baizhou Li, Xiaoyan Zhang and Meili Zhang

Processes 2019, 7(7), 443; https://doi.org/10.3390/pr7070443 - 12 Jul 2019

Cited by 30 | Viewed by 4771

Abstract

With the deep integration of supply chain with Internet and Internet of things, it is an important way for enterprises to win market competition and seek sustainable development to develop green new products through external green supply chain integration (GSCI). This study established [...] Read more.

With the deep integration of supply chain with Internet and Internet of things, it is an important way for enterprises to win market competition and seek sustainable development to develop green new products through external green supply chain integration (GSCI). This study established a unified research framework of external GSCI, knowledge spiral (KS), green new product development (NPD), and top management’s environmental awareness (TMEA). Structural equation modeling and analytic hierarchy process are used to explore the mechanism of the established research framework. The research results of this paper are as follows: (i) Green supplier integration (SI) and green consumer integration (CI) have significant positive effects on green NPD speed (GS), green NPD quality (GQ), and KS, and KS has a significant positive effect on GS and GS, respectively. Compared with green CI, green SI has a greater impact on KS, GS, and GQ. In addition, compared with GS, KS has a greater impact on GQ; (ii) KS has a significant partial mediating effect in the relationship between green CI, GS, and GQ. Compared with GS, KS has stronger mediating effect between green CI and GQ. Compared with green SI, the equivalent KS capability is more significant in integrating green customer information; (iii) TMEA has a significant moderating effect on the relationship between KS, and GQ and has no significant moderating effect on the relationship between KS and GS. Future research will analyze the mediating effect of the four dimensions of KS in the relationship between external GSCM and the green NPD speed and green NPD quality. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

13 pages, 1235 KiB

Open AccessArticle

A Fuzzy Multicriteria Decision-Making (MCDM) Model for Sustainable Supplier Evaluation and Selection Based on Triple Bottom Line Approaches in the Garment Industry

by Chia-Nan Wang, Ching-Yu Yang and Hung-Chun Cheng

Processes 2019, 7(7), 400; https://doi.org/10.3390/pr7070400 - 27 Jun 2019

Cited by 53 | Viewed by 6955

Abstract

Vietnam’s garment industry is facing many challenges, including domestic competition and the global market. The free trade agreement, which Vietnam signed, includes environmental barriers, sustainable development, and green development. The agreement further requires businesses to make efforts to improve not only product quality [...] Read more.

Vietnam’s garment industry is facing many challenges, including domestic competition and the global market. The free trade agreement, which Vietnam signed, includes environmental barriers, sustainable development, and green development. The agreement further requires businesses to make efforts to improve not only product quality but also the production process. In cases when enterprises cause environmental pollution in the production process and do not apply solutions to reduce waste, save energy, and natural resources, there is a risk of no longer receiving orders or orders being rejected, especially orders from the world’s major branded garment companies. In this research, the authors propose a multicriteria decision-making model (MCDM) for optimizing the supplier evaluation and selection process for the garment industry using sustainability considerations. In the first stage of this research, all criteria affecting supplier selection are determined by a triple bottom line (TBL) model (economic, environmental, and social aspects) and literature reviews; in addition, the fuzzy analytic hierarchy process (FAHP) method was utilized to identify the weight of all criteria in the second stage. The technique for order preference by similarity to an ideal solution (TOPSIS) is a multicriteria decision analysis method, which is used for ranking potential suppliers in the final stage. As a result, decision-making unit 10 (DMU/10) is found to be the best supplier for the garment industry. The contribution of this research includes modeling the supplier selection decision problem based on the TBL concept. The proposed model also addresses different complex problems in supplier selection, is a flexible design model for considering the evaluation criteria, and is applicable to supplier selection in other industries. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

14 pages, 1945 KiB

Open AccessFeature PaperArticle

Analysis of the Trends in Biochemical Research Using Latent Dirichlet Allocation (LDA)

by Hee Jay Kang, Changhee Kim and Kyungtae Kang

Processes 2019, 7(6), 379; https://doi.org/10.3390/pr7060379 - 18 Jun 2019

Cited by 35 | Viewed by 5274

Abstract

Biochemistry has been broadly defined as “chemistry of molecules included or related to living systems”, but is becoming increasingly hard to be distinguished from other related fields. Targets of its studies evolve rapidly; some newly emerge, disappear, combine, or resurface themselves with a [...] Read more.

Biochemistry has been broadly defined as “chemistry of molecules included or related to living systems”, but is becoming increasingly hard to be distinguished from other related fields. Targets of its studies evolve rapidly; some newly emerge, disappear, combine, or resurface themselves with a fresh viewpoint. Methodologies for biochemistry have been extremely diversified, thanks particularly to those adopted from molecular biology, synthetic chemistry, and biophysics. Therefore, this paper adopts topic modeling, a text mining technique, to identify the research topics in the field of biochemistry over the past twenty years and quantitatively analyze the changes in its trends. The results of the topic modeling analysis obtained through this study will provide a helpful tool for researchers, journal editors, publishers, and funding agencies to understand the connections among the diverse sub-fields in biochemical research and even see how the research topics branch out and integrate with other fields. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

16 pages, 4449 KiB

Open AccessArticle

Performance Evaluation of Sustainable Soil Stabilization Process Using Waste Materials

by Muhammad Aamir, Zarnish Mahmood, Aqsa Nisar, Amjad Farid, Tanveer Ahmed Khan, Mudassir Abbas, Muhammad Ismaeel, Syyed Adnan Raheel Shah and Muhammad Waseem

Processes 2019, 7(6), 378; https://doi.org/10.3390/pr7060378 - 18 Jun 2019

Cited by 29 | Viewed by 10506

Abstract

The process of soil stabilization is a fundamental requirement before road infrastructure development is possible. Different binding materials have been used worldwide as soil stabilizers. In this study, water treatment waste (i.e., alum sludge (AS)) was used as a soil stabilizer. Alum sludge [...] Read more.

The process of soil stabilization is a fundamental requirement before road infrastructure development is possible. Different binding materials have been used worldwide as soil stabilizers. In this study, water treatment waste (i.e., alum sludge (AS)) was used as a soil stabilizer. Alum sludge can work not only as a low-cost soil stabilizer but also can solve the problem of waste management at a large scale. Utilization of alum waste can be a sustainable solution and environmentally friendly exercise. Thus, in consideration of the pozzolanic properties of alum, it was applied as a binder, similar to cement or lime, to stabilize the soil with the addition of 2%, 4%, 6%, 8%, and 10% of dry soil by weight. To analyze the resulting improvement in soil strength, the California Bearing Ratio (CBR) test was conducted in addition to three other tests (i.e., particle size analysis, Atterberg’s limits test, and modified proctor test). The soil bearing ratio was significantly improved from 6.53% to 16.86% at the optimum level of an 8% addition of alum sludge. Furthermore, the artificial neural networks (ANNs) technique was applied to study the correlations between the CBR and the physical properties of soil, which showed that, at 8% optimum alum sludge, maximum dry density, optimum moisture content, and plasticity index were also at maximum levels. This study will help in providing an eco-friendly soil stabilization process as well as a waste management solution. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Graphical abstract

15 pages, 1007 KiB

Open AccessArticle

Control Charts for Monitoring Process Capability Index Using Median Absolute Deviation for Some Popular Distributions

by Muhammad Aslam, G. Srinivasa Rao, Ali Hussein AL-Marshadi, Liaquat Ahmad and Chi-Hyuck Jun

Processes 2019, 7(5), 287; https://doi.org/10.3390/pr7050287 - 15 May 2019

Cited by 21 | Viewed by 5340

Abstract

A control chart monitoring the process capability index (PCI) using median absolute deviation (MAD) is proposed to analyze the industrial process performance. Extensive simulation studies were carried out to evaluate the performance of MAD-based PCI control charts under the low, moderate, and high [...] Read more.

A control chart monitoring the process capability index (PCI) using median absolute deviation (MAD) is proposed to analyze the industrial process performance. Extensive simulation studies were carried out to evaluate the performance of MAD-based PCI control charts under the low, moderate, and high asymmetric conditions when the process characteristic follows Weibull, log-normal, and gamma distributions. The performance of the proposed control charts was evaluated based on the average run lengths. The practical implementation of the proposed charts was also illustrated with industrial data. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

14 pages, 1324 KiB

Open AccessArticle

Integer Programming Scheduling Model for Tier-to-Tier Shuttle-Based Storage and Retrieval Systems

by Xiaofeng Zhao, Yanyan Wang, Yunge Wang and Ke Huang

Processes 2019, 7(4), 223; https://doi.org/10.3390/pr7040223 - 19 Apr 2019

Cited by 14 | Viewed by 3995

Abstract

Shuttle-based storage and retrieval systems (SBS/RSs), a new type of “part-to-picker” system, have attracted public attention because of their flexibility and robustness. The systems consist of two sub-systems—shuttles and lifts—which are responsible for horizontal movements and vertical movements, respectively. SBS/RSs are categorized into [...] Read more.

Shuttle-based storage and retrieval systems (SBS/RSs), a new type of “part-to-picker” system, have attracted public attention because of their flexibility and robustness. The systems consist of two sub-systems—shuttles and lifts—which are responsible for horizontal movements and vertical movements, respectively. SBS/RSs are categorized into tier-to-tier shuttles and tier-captive shuttles. This paper mainly researches SBS/RSs with tier-to-tier shuttles. New challenges have emerged since the commercial simulation-based optimization software has become widely applied for, for instance, task scheduling problems. Specifically, to decrease the idle time of lifts and the waiting time of shuttles, an integer programming scheduling model is proposed to minimize total task time with constraints on orders and devices. The Gurobi linear programming solver was utilized to obtain the optimal order sequence and the shortest operation time. The overall system efficiency was improved using our model. Moreover, the results are significant for reducing capital investment and operating cost. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

37 pages, 789 KiB

Open AccessArticle

Designing Supply Networks in Automobile and Electronics Manufacturing Industries: A Multiplex Analysis

by Myung Kyo Kim and Ram Narasimhan

Processes 2019, 7(3), 176; https://doi.org/10.3390/pr7030176 - 26 Mar 2019

Cited by 9 | Viewed by 4388

Abstract

This study investigates the process of how the original equipment manufacturers (OEMs) in automobile and consumer electronics industries design their supply networks. In contrast to the sociological viewpoint, which regards the emergence of networks as a social and psychological phenomenon occurring among non-predetermined [...] Read more.

This study investigates the process of how the original equipment manufacturers (OEMs) in automobile and consumer electronics industries design their supply networks. In contrast to the sociological viewpoint, which regards the emergence of networks as a social and psychological phenomenon occurring among non-predetermined individuals, this paper attempts to provide a strategic supply network perspective that views the supply network as a strategic choice made by an OEM. Anchored in the multiplex investigation of supply network architectures, this study looks into the following specific questions: (1) Are an OEM’s strategic intent choices associated with supply network architecture and (2) If so, what differential effects do those strategic intents have on the architectural properties of the supply network? Further field investigations were conducted to provide deeper insights into the quantitative and qualitative findings from statistical analyses. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

16 pages, 1484 KiB

Open AccessArticle

Air-Core-Liquid-Ring (ACLR) Atomization: Influences of Gas Pressure and Atomizer Scale Up on Atomization Efficiency

by Marc O. Wittner, Heike P. Karbstein and Volker Gaukel

Processes 2019, 7(3), 139; https://doi.org/10.3390/pr7030139 - 6 Mar 2019

Cited by 10 | Viewed by 4475

Abstract

Air-core-liquid-ring (ACLR) atomizers present a specific type of internal mixing pneumatic atomizers, which can be used for efficient atomization of high viscous liquids. Generally, atomization efficiency is considered as a correlation between energy input and resulting droplet size. In pneumatic atomization, air-to-liquid ratio [...] Read more.

Air-core-liquid-ring (ACLR) atomizers present a specific type of internal mixing pneumatic atomizers, which can be used for efficient atomization of high viscous liquids. Generally, atomization efficiency is considered as a correlation between energy input and resulting droplet size. In pneumatic atomization, air-to-liquid ratio by mass (ALR) is commonly used as reference parameter of energy input. However, the pressure energy of the atomization gas is not considered in the calculation of ALR. In internal mixing ACLR atomizers, it can be assumed that this energy contributes to liquid disintegration by expansion of the gas core after exiting the atomizer. This leads to the hypothesis that droplet sizes decrease with increasing gas pressure at constant ALR. Therefore, the use of volumetric energy density (E_V) as a reference parameter of energy input was investigated at different gas pressures between 0.4 and 0.8 MPa. Furthermore, scale up-related influences on the atomization efficiency of ACLR atomization were investigated by use of an atomizer with enlarged exit orifice diameter. We can conclude that E_V can be applied as a reference parameter of ACLR atomization processes with different gas pressures. However, within the range investigated no clear influence of gas pressure on atomization efficiency was found. Up-scaling of ACLR atomizers allows production of similar droplet sizes, but atomization efficiency decreases with increasing exit orifice diameter. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

27 pages, 4147 KiB

Open AccessArticle

Determination of KOSGEB Support Models for Small- and Medium-Scale Enterprises by Means of Data Envelopment Analysis and Multi-Criteria Decision Making Methods

by Ali Sevinç and Tamer Eren

Processes 2019, 7(3), 130; https://doi.org/10.3390/pr7030130 - 2 Mar 2019

Cited by 8 | Viewed by 3841

Abstract

Small- and Medium-Scale Enterprises (SMEs) act as catalysts in the general economy with regard to their added value. Support programs have been designed by the government through the Small and Medium Enterprises Development and Support Administration KOSGEB) and other institutions in order to [...] Read more.

Small- and Medium-Scale Enterprises (SMEs) act as catalysts in the general economy with regard to their added value. Support programs have been designed by the government through the Small and Medium Enterprises Development and Support Administration KOSGEB) and other institutions in order to further the general economic contributions of such enterprises. However, there is no method for using support models according to a productivity and effectiveness principle. This causes serious wastes of both resources and time. In this study, the problem of applying support models to improve the most critical problems of SMEs was discussed. As a place of application, 82 firms registered to the Konya Chamber of Industry were selected for the automotive supplier industry. Firstly, a productivity evaluation of companies was performed by a data envelopment analysis (DEA). Firms were grouped into A, B1, B2, C1, and C2 according to their activity scores. Using an Analytical Hierarchy Process (AHP), the order of KOSGEB support was found using the Technique for Order Preference by Similarity to Ideal Solution method (TOPSIS). Thus, firms will be able to focus on their most pressing problems, as well as enabling the efficient use of resources A: Small- and Medium-Scale Enterprises Improvement and Support Program (KOBIGEL) support model, B1: Logistic support model, B2: KOBIGEL support model, C1: Test analysis and calibration support model, and C2: Test analysis and calibration support model. This means that these support models are required in the first place for group companies.A KOBIGEL support model is the provincial rank for A group companies. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

16 pages, 3790 KiB

Open AccessArticle

Response Surface Method in the Optimization of a Rotary Pan-Equipped process for Increased Efficiency of Slow-Release Coated Urea

by Farahnaz Eghbali Babadi, Robiah Yunus, Ali Abbasi and Salman Masoudi Soltani

Processes 2019, 7(3), 125; https://doi.org/10.3390/pr7030125 - 28 Feb 2019

Cited by 11 | Viewed by 4719

Abstract

The high solubility of urea in water and its consequent leaching into the soil adversely prevents its full assimilation by plants. An improved slow-release process could effectively minimise the loss of fertilizer material and thus mitigate the associated environmental pollution. In this study, [...] Read more.

The high solubility of urea in water and its consequent leaching into the soil adversely prevents its full assimilation by plants. An improved slow-release process could effectively minimise the loss of fertilizer material and thus mitigate the associated environmental pollution. In this study, the effects of the operational variables on the efficiency of the urea coating process in a rotary pan have been systematically analysed. A mixture of gypsum-sulphur was used as the coating material with refined water as a binder. In order to comprehensively investigate the impact of each process variable on the efficiency and any potential interactions between them, the effects of particle size, coating material percentage, rotational speed of the pan, spray flow rate and the amount of sprayed water were investigated and analysed via a central composite design of experiments (DoE). The second-order polynomial model provided the best correlation for the experimental data. The predictive model was then used to estimate the efficiency of the coated urea as a function of the statistically-significant variables. The results revealed an increase in the efficiency of the coated urea from 22% to 35% (i.e., ~59%) when prepared under the optimum process conditions. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Graphical abstract

12 pages, 6728 KiB

Open AccessArticle

Discrete Element Method Model Optimization of Cylindrical Pellet Size

by Jiri Rozbroj, Jiri Zegzulka, Jan Necas and Lucie Jezerska

Processes 2019, 7(2), 101; https://doi.org/10.3390/pr7020101 - 15 Feb 2019

Cited by 8 | Viewed by 4077

Abstract

The DEM (Discrete Element Method) is one option for studying the kinematic behaviour of cylindrical pellets. The DEM experiments attempted to optimize the numerical model parameters that affected time and velocity as a cylindrical vessel emptied. This vessel was filled with cylindrical pellets. [...] Read more.

The DEM (Discrete Element Method) is one option for studying the kinematic behaviour of cylindrical pellets. The DEM experiments attempted to optimize the numerical model parameters that affected time and velocity as a cylindrical vessel emptied. This vessel was filled with cylindrical pellets. Optimization was accomplished by changing the coefficient of friction between particles and selecting the length accuracy grade of the sample cylindrical pellets. The initial state was a series of ten vessel-discharge experiments evaluated using PIV (Particle Image Velocimetry). The cylindrical pellet test samples were described according to their length in three accuracy grades. These cylindrical pellet length accuracy grades were subsequently used in the DEM simulations. The article discusses a comparison of the influence of the length accuracy grade of cylindrical pellets on optimal calibration of time and velocity when the cylindrical vessel is emptied. The accuracy grade of cylindrical pellet length in the DEM sample plays a significant role in relation to the complexity of a created simulation. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Graphical abstract

14 pages, 957 KiB

Open AccessArticle

A Systems Engineering Approach to Performance-Based Maintenance Services Design

by Maria Holgado

Processes 2019, 7(2), 59; https://doi.org/10.3390/pr7020059 - 23 Jan 2019

Cited by 11 | Viewed by 4928

Abstract

Traditionally, industrial services have been mainly transaction-based, i.e., the equipment user pays the service provider for getting a job done or providing assistance and support for equipment operations. Recently, a trend has emerged of increasing the relational perspective of these services, which are [...] Read more.

Traditionally, industrial services have been mainly transaction-based, i.e., the equipment user pays the service provider for getting a job done or providing assistance and support for equipment operations. Recently, a trend has emerged of increasing the relational perspective of these services, which are becoming more oriented towards customer value and service performance levels. Among these emergent industrial services, performance-based services represent an opportunity for equipment manufacturers to transform their service offerings towards more relational and customer-oriented services. The purpose of this work is to study the design of a generic performance-based maintenance service under a novel perspective given by systems engineering. This paper is intended to serve as a starting point to fully understand this type of services and to develop a method that can support equipment manufacturers who wish to advance their service offerings. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

16 pages, 2602 KiB

Open AccessArticle

Analysis of Influencing Factors of Occupational Safety and Health in Coal Chemical Enterprises Based on the Analytic Network Process and System Dynamics

by Kai Yu, Lujie Zhou, Chen Hu, Linlin Wang and Weiqiang Jin

Processes 2019, 7(1), 53; https://doi.org/10.3390/pr7010053 - 21 Jan 2019

Cited by 14 | Viewed by 5766

Abstract

In the production process of coal chemical enterprises, there are factors such as dust, poisons, as well as toxic and harmful gases, which seriously restrict the safety and health of employees. It is urgent to strengthen research on occupational safety and health (OSH) [...] Read more.

In the production process of coal chemical enterprises, there are factors such as dust, poisons, as well as toxic and harmful gases, which seriously restrict the safety and health of employees. It is urgent to strengthen research on occupational safety and health (OSH) of coal chemical enterprises. Research on the influencing factors is very important to improve the level of OSH in coal chemical enterprises. Therefore, this paper analyzed the factors affecting OSH of coal chemical enterprises from four aspects: “human–machine–environment–management”. Then, an influencing factor indicator system was constructed. The weights of the indicator were analyzed using the Analytic Network Process (ANP). On this basis, the primary and secondary indicators of the influencing factors were ranked. Subsequently, the weights of ANP were taken as the influence coefficient between variables, and the System Dynamics (SD) model of OSH control measures was established and analyzed. According to the weights of ANP and the results of SD simulation, management and control measures were proposed to provide theoretical support and method guidance for improving the level of OSH in coal chemical enterprises. Finally, the research results were experimentally applied to coal chemical enterprises. The research results of the paper will improve the level of OSH in coal chemical enterprises of both theoretical and practical applications. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

23 pages, 2274 KiB

Open AccessArticle

Robust Scheduling Optimization Model for Multi-Energy Interdependent System Based on Energy Storage Technology and Ground-Source Heat Pump

by Zhongfu Tan, Hongwu Guo, Hongyu Lin, Qingkun Tan, Shenbo Yang, De Gejirifu, Liwei Ju and Xueying Song

Processes 2019, 7(1), 27; https://doi.org/10.3390/pr7010027 - 8 Jan 2019

Cited by 9 | Viewed by 3639

Abstract

The energy consumed by buildings makes up a significant part of total social energy consumption. The energy use rate of the traditional cooling and heating unit is low. A distributed cooling, heating, and power (CHP) system can achieve cascade use of energy and [...] Read more.

The energy consumed by buildings makes up a significant part of total social energy consumption. The energy use rate of the traditional cooling and heating unit is low. A distributed cooling, heating, and power (CHP) system can achieve cascade use of energy and reduce the long-distance transportation of energy. Along with the wide use of ground-source heat pumps and energy storage technology, the combined cooling, heating, and power (CCHP) system coupled with a ground-source heat pump and energy storage technology is increasingly being used. Firstly, we proposed the construction of a CCHP system driven by distributed energy resources (DERs) including three subsystems of an electricity subsystem, a CCHP subsystem and an auxiliary heating subsystem as the object of study in this paper. Besides, with the goals of reducing carbon emissions, increasing energy efficiency, and minimizing system cost, a constraint mechanism based on the DOM-PSO (dynamic object method/particle swarm optimization) algorithm was applied. Finally, taking Tianjin Eco-City as an example, we used the PSO algorithm to analyze the operating characteristics of the cold and power cogeneration system under the uncertainty of the wind power output. The simulation results show that the joint optimization mode operation strategy can balance the results of different optimization modes by increasing the robust coefficient of wind power. Of all scenarios examined, the CCHP system coupled with the ground-source heat pump and energy storage technology performed best. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

19 pages, 3478 KiB

Open AccessArticle

New Technical Parameters and Operational Improvements of the Metal Oxide Varistors Manufacturing Process

by Flaviu Mihai Frigura-Iliasa, Sorin Musuroi, Ciprian Sorandaru and Doru Vatau

Processes 2019, 7(1), 18; https://doi.org/10.3390/pr7010018 - 2 Jan 2019

Cited by 14 | Viewed by 4523

Abstract

At the beginning, this article details the manufacturing procedures for varistor materials. Starting from the initial composition of two large series of varistors (those with two additive oxides and those with five additive oxides), there is a major overview of the main stages [...] Read more.

At the beginning, this article details the manufacturing procedures for varistor materials. Starting from the initial composition of two large series of varistors (those with two additive oxides and those with five additive oxides), there is a major overview of the main stages of the technological process and the equipment used for the production, emphasizing the technological changes that were made. The article continues with the study of the influence of the sintering pressure and the sintering temperature on the electrical properties of the varistor materials made before. There were two experimental series of 7 varistors, one series based on 2 additive oxides and one based on 5 additive oxides. Each varistor of these series was sintered at another temperature, the fundamental purpose being to determine an optimal sintering temperature for each chemical composition. A second activity consisted of manufacturing two more series of varistors with the same chemical composition (2 oxides and 5 additive oxides), which were sintered at two different pressures, for having a set of conclusions on the influence of sintering pressure on the electric performances. All conclusions are underlying a new process for manufacturing metal oxide based varistors. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

12 pages, 862 KiB

Open AccessArticle

A Multi-Criteria Decision-Making (MCDM) Approach Using Hybrid SCOR Metrics, AHP, and TOPSIS for Supplier Evaluation and Selection in the Gas and Oil Industry

by Chia-Nan Wang, Ying-Fang Huang, I-Fang Cheng and Van Thanh Nguyen

Processes 2018, 6(12), 252; https://doi.org/10.3390/pr6120252 - 6 Dec 2018

Cited by 52 | Viewed by 8014

Abstract

Suppliers are extremely important in business operations. The supplier ensures the supply of materials, raw materials, commodities, etc. in sufficient quantity, quality, stability, and accuracy to meet the requirements of production and business with low costs and on-time deliveries. Therefore, selecting and managing [...] Read more.

Suppliers are extremely important in business operations. The supplier ensures the supply of materials, raw materials, commodities, etc. in sufficient quantity, quality, stability, and accuracy to meet the requirements of production and business with low costs and on-time deliveries. Therefore, selecting and managing good suppliers is a prerequisite for organizing the production of quality products as desired, according to the schedule, and with reasonable prices and competitiveness in the market. It is also important to gain the support of suppliers in order to continue to improve and achieve more as a business. The evaluation and selection of a supplier is a Multi-Criteria Decision-Making (MCDM) issue, in which the decision-maker is faced with both qualitative and quantitative factors. In this research, the authors propose an MCDM model using a hybrid of Supply Chain Operations Reference metrics (SCOR metrics), the Analytic Hierarchy Process (AHP) model, and the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) approach for supplier evaluation and selection in the gas and oil industry. Using literature reviews on SCOR metrics, all criteria that impact supplier selection are defined in the first stage, the AHP model is applied to determine the weight of each factor in the second stage, and the optimal supplier is presented in final stage using the TOPSIS model. As a result, Decision-Making Unit 5 (DMU-05) is found to be the best supplier for the gas and oil industry in this research. The contribution of this work is to propose a new hybrid MCDM model for supplier selection in the gas and oil industry. This research also introduces a useful tool for supplier selection in other industries. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Figure 1

16 pages, 2900 KiB

Open AccessArticle

Wheat Germ Drying with Different Time-Temperature Combinations in a Fluidized Bed Dryer

by Der-Sheng Chan and Meng-I Kuo

Processes 2018, 6(12), 245; https://doi.org/10.3390/pr6120245 - 28 Nov 2018

Cited by 7 | Viewed by 5765

Abstract

The development of an effective drying performance of the fluidized bed dryer (FBD) is crucial to reduce drying costs. The objective of this study was to investigate the drying performance of wheat germ (WG) with different time-temperature combinations in the FBD. The WG [...] Read more.

The development of an effective drying performance of the fluidized bed dryer (FBD) is crucial to reduce drying costs. The objective of this study was to investigate the drying performance of wheat germ (WG) with different time-temperature combinations in the FBD. The WG was dried at different set temperatures of 80, 100 and 120 °C. The moisture content (MC) and water activity (WA) of WG were measured. A mathematical model was proposed to develop an optimal drying condition. The changes in the MC of WG during drying in the FBD could be divided into the decreased period, the dynamic equilibrium period and the increased period. The product temperature of 45 °C and WA of 0.3 of WG drying could be attained by different time-temperature combinations. The mathematical model, which was developed in conjunction with different time-temperature combinations, could predict the dehydration time and the condensation time of WG for optimization the drying conditions. The WG dehydration at the heating stage and the WG condensation at the cooling stage could also be evaluated by the dehydration flux and the condensation flux, respectively. The optimal drying performance of WG exists in a compromise between promoting dehydration and reducing condensation. Information obtained from the analysis of dehydration flux and condensation flux with experimental data and simulation gave the guidelines for performing an effective drying of WG in the FBD. Full article

(This article belongs to the Special Issue Performance Measurement and Optimization for Sustainable Production Processes Improvement)

► Show Figures

Graphical abstract

Journal Menu

Journal Browser

Performance Measurement and Optimization for Sustainable Production Processes Improvement

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Benefits of Publishing in a Special Issue

Published Papers (25 papers)

Editorial

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI