Comparative Analysis of the Implementation of the SMED Method on Selected Production Stands

Nowadays, companies are looking for newer and newer methods in order to increase their efficiency and effectiveness. Many of them decide to implement Lean Manufacturing philosophy because the benefits of the introduction of this philosophy apply not only to the industrial but also to the financial and commercial areas. These changes can increase the efficiency of production realized with small investments, improve product quality, reduce inventory as well as material consumption. This philosophy can shorten the delivery time and product quality what leads to the increased customer satisfaction and enhances the competitiveness of enterprises. One of the tools of Lean Manufacturing is the Single Minute Exchange of Die (SMED) method. The implementation of this method reduces machines changeover time, which is a waste. This method makes it possible to implement a continuous flow of the product without long waiting times and, most importantly, without any performance loss. The results of the implementation of the SMED method on several different production work stands are presented in this work. The selected stands differ in type (conventional, semi-automatic, automatic) and their role in a production process (bottlenecks, support process). The work, by means of indicative evaluation, assesses the ability to increase the efficiency of machines for the analysed production work stands. The work indicates the effects a company may expect having decided to implement the SMED method for the production areas that are a part of either the main or support processes

Depression and anxiety mediate the relationship between the retrospectively measured symptoms of premenstrual disorders and negative but not positive psychotic‑like experiences

The aim of this study was to examine the relationship between retrospectively measured premenstrual symptoms and subclinical forms of positive and negative psychotic symptoms (psychotic-like experiences; PLEs). It was hypothesised that subjective intensity of the symptoms of premenstrual disorders predicts PLEs frequency and that this relationship is mediated by anxiety and depression. The study sample comprised 108 non-clinical subjects. Study variables were assessed with self-report questionnaires: the Premenstrual Symptoms Screening Tool (PSST); the Beck Depression Inventory Second Edition (BDI-II); the State-Trait Anxiety Inventory (STAI; trait sub-scale); the Community Assessment of Psychic Experiences (CAPE). Regression and mediation analyses were performed. The PSST scores were significantly and positively associated with psychotic-like experiences frequency. The relation was stronger for positive PLEs. Anxiety and depression partially mediated the relationship between premenstrual symptoms and negative PLEs, but not between premenstrual symptoms and positive PLEs. Although the design of the study does not allow to infer causality, it demonstrates strong, positive relationship between the symptoms of premenstrual disorders and psychotic-like experiences. The relationship between premenstrual disorders and negative PLEs seems to be partially based on a general psychopathological factor. Further longitudinal studies are needed to test whether premenstrual disturbances increase risk of psychotic symptoms

Systems engineering: availability and reliability

Current trends in Industry 4 [...

Identification of the critical enablers for perishable food supply chain using deterministic assessment models

Today’s perishable food supply chains must be resilient to handle volatile demands, environmental restrictions, and disruptions in order to meet customers’ requirements. The enablers of the perishable food supply chain have not yet been explored. In this paper, a bibliometric systematic literature review has been conducted to identify the articles related to the perishable food supply chain. Next, with these identified articles, a map is created with bibliographic data using Vosviewer network visualization software, and then the enablers were identified by conducting keyword co-occurrence analysis. Later, a total interpretive structural modeling (TISM) is employed to analyze the interrelationships among enablers and then determine each enabler’s hierarchies, further representing them in a diagraph. Finally, the identified enablers are classified using cross-impact matrix multiplication applied to classification (MICMAC) analysis, and the graph is plotted. The results obtained from the deterministic assessment model provide the critical enablers for the perishable food supply chain. The obtained critical enablers and their hierarchies provide valuable insights for researchers in the context of perishable food supply chain for further study.The authors are grateful to FCT - Fundação para a Ciência e Tecnologia who financially supported this work through the RD Units Project Scope: UIDP/04077/2020 and UIDB/04077/2020

A systematic simulation-based multi-criteria decision-making approach for the evaluation of semi-fully flexible machine system process parameters

Current manufacturing system health management is of prime importance due to the emergence of recent cost-effective and -efficient prognostics and diagnostics capabilities. This paper investigates the most used performance measures viz. Throughput Rate, Throughput Time, System Use, Availability, Average Stay Time, and Maximum Stay Time as alternatives that are responsible for the diagnostics of manufacturing systems during real-time disruptions. We have considered four different configurations as criteria on which to test with the proposed integrated MCDM (Multi-Criteria Decision-Making)-TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution)-based simulation approach. The main objective of this proposed model is to improve the performance of semi–fully flexible systems and to maximize the production rate by ranking the parameters from most influenced to least. In this study, first, the performance of the considered process parameters are analyzed using a simulation approach, and furthermore the obtained results are validated using real-time experimental results. Thereafter, using an Entropy method, the weights of each parameter are identified and then the MCDM-based TOPSIS is applied to rank the parameters. The results show that Throughput tTme is the most affected parameter and that Availability, average stay time, and max stay time are least affected in the case of no breakdown of machine condition. Similarly, Throughput Time is the most affected parameter and Maximum Stay Time is the least affected parameter in the case of the breakdown of machine condition. Finally, the rankings from the TOPSIS method are compared with the PROMETHEE method rankings. The results demonstrate the ability to understand system behavior in both normal and uncertain conditions.This work has been, also, supported by the FCT within the RD Units Project Scope: UIDP/04077/2020 and UIDB/04077/2020

Negative affectivity moderates the relationship between attentional control and focused skin picking

Very little is known about the cognitive functioning of people with body-focused repetitive behaviours and the few existing studies provide mixed findings. The aim of this study was to investigate the interplay between attentional control, negative affectivity, and focused skin picking. We hypothesized that the control of attention is associated with focused style of skin picking and that this relationship is moderated by negative affectivity. The final sample consisted of 273 non-clinical subjects (79% women) aged 18 to 54 years; study variables were assessed using questionnaires. Moderation analysis was conducted, followed by a simple slope analysis, and the Johnson-Neyman technique was used to probe the interaction effect. We found that at the low level of negative affectivity, the relationship between attentional control and focused skin picking is negative, but not at the higher levels of this trait. Interestingly, when negative affectivity reaches very high intensity, the association between attentional control and skin picking becomes positive. This relationship seems to be quite complex and may depend on the way that cognitive abilities are used by the individual, as well as on the stage of cognitive processing that they are applied to. Further studies using behavioural measures of attention are needed to better understand this issue

From lean to sustainable manufacturing : an overview

PURPOSE: The purpose of the research is to present the comparison and connection between three manufacturing paradigms, Lean, Green, and Sustainable Manufacturing.DESIGN/METHODOLOGY/APPROACH: The methodology of the research is based on the literature review of three paradigms, including, definitions, methods and tools, as well as main challenges.FINDINGS: Transition towards Sustainable Manufacturing has been taking place in an evolutionary way and may be traced in the context of changes in production paradigms. The production paradigms presented in paper do not cover all examples of paradigms classification contained in the literature, since, they only indicate the way to learn the theories and challenges that the scientific community and economic practitioners must face.PRACTICAL IMPLICATIONS: Lean and green methods and tools support the realization of sustainable manufacturing processes challenges.ORIGINALITY/VALUE: The paper presents synergy between every production paradigms. Every new paradigm generally considers the objectives and approaches of the previous one, so integrating the lean and green approach is a natural consequence. The combination of these two concepts enables achieving a synergetic effect even if a trade-off and balance of divergent goals. The shift from conventional manufacturing practices to more sustainable practices has led to better compliance with regulations and standards in order to enhance the corporate and brand image while pursuing economic benefits and environmental and societal responsibility.peer-reviewe

Validation and psychometric properties of the Polish version of the Skin Picking Scale-Revised

The Skin Picking Scale-Revised (SPS-R) is an 8-item self-report measure of skin picking behaviors. It includes two subscales related to skin picking symptom severity and picking-related impairments. The study aimed to assess the psychometric properties of the Polish version of the SPS-R in a sample of adults reporting skin picking. The sample of 764 participants was recruited from the general population through an online survey. Among them, 159 meet the criteria of pathological skin picking applied in the original SPS-R validation study, and 57 endorsed all of the DSM-5 criteria for excoriation disorder. The SPS-R was back-translated into Polish. Factor structure, reliability, convergent and divergent validity, and diagnostic accuracy were assessed. Confirmatory factor analyses revealed a two-factor structure of the scale. High internal consistency and convergent and divergent validity were confirmed for the total score as well as for the subscales. High prognostic ability of the SPS-R total score was also demonstrated using ROC analysis: ≥5 was accepted as an optimal cut-off point for distinguishing skin picking sufferers from healthy controls. The Polish version of the SPS-R shows good psychometric properties and appears to be a reliable measure of skin picking symptoms and picking-related impairment

Technical risk assessment for the safe design of a man-rider chair lift system

Underground mining is a difficult area for miners to work. Miners must go to the working faces by walking, which is not only time consuming but also physically demanding. In mines, a man-rider chair lift system (MRCL) has been developed to alleviate the strain stresses caused by walking lengthy and uneven distances up to the working faces. All parameters, including horizontal and vertical distances, variation and inclination of underground mines, slope forces considering the weight of persons and chair, forces acting towards return and drive unit, curves angles, power to operate, and rope safety factor, are calculated mathematically while modelling a man-rider chair lift system for both the installation and extension phases. We analyzed the analytical approach in conjunction with practical installation of the man-rider chair lift system to establish if the installation and extension of MRCL is genuinely feasible in the current scenario. We also created a simulation model of steel wire rope in Creo 8.0 for analyzing the various stresses on it with the Ansys R 16.2 software. In both phase I and phase II, the factor of safety is above that recommended, and the system is a hundred percent reliable, risk-free, and safe for operation.The authors are grateful to FCT—Fundação para a Ciência e Tecnologia (Portugal)—who partially financially supported this work through the RD Units Project Scope: UIDP/04077/2020 and UIDB/04077/2020

The Arabidopsis condensin CAP‐D subunits arrange interphase chromatin

Condensins are best known for their role in shaping chromosomes. Other functions such as organizing interphase chromatin and transcriptional control have been reported in yeasts and animals, but little is known about their function in plants. To elucidate the specific composition of condensin complexes and the expression of CAP-D2 (condensin I) and CAP-D3 (condensin II), we performed biochemical analyses in Arabidopsis. The role of CAP-D3 in interphase chromatin organization and function was evaluated using cytogenetic and transcriptome analysis in cap-d3 T-DNA insertion mutants. CAP-D2 and CAP-D3 are highly expressed in mitotically active tissues. In silico and pull-down experiments indicate that both CAP-D proteins interact with the other condensin I and II subunits. In cap-d3 mutants, an association of heterochromatic sequences occurs, but the nuclear size and the general histone and DNA methylation patterns remain unchanged. Also, CAP-D3 influences the expression of genes affecting the response to water, chemicals, and stress. The expression and composition of the condensin complexes in Arabidopsis are similar to those in other higher eukaryotes. We propose a model for the CAP-D3 function during interphase in which CAP-D3 localizes in euchromatin loops to stiffen them and consequently separates centromeric regions and 45S rDNA repeats