Volume 9 - 2018

Nanostructure of Orthodontic Adhesives

Vladan D. Mirjanić, Đorđe D. Mirjanić

Nanostructure of the orthodontic adhesives for bonding brackets to teeth most frequently used nowadays in clinical procedure is analyzed by way of Atomic Force Microscopy (AFM). Study was done on 5 orthodontic adhesives. After determining the properties of adhesive, a correlation was determined between the nanostructure of tested adhesive and the strength of tooth bracket interface. Based on AFM images of analyzed adhesives, and by way of correlations of arithmetic means of debonding strength (I) and the average adhesive roughness (Ra, Rq, Rz), it has been concluded that with an increase of average adhesive roughness’s, increases the debonding strength. (I). It was observed that with all the roughness parameters (Ra, Rz, and Rq), the strongest bond and theweakest bond was determined Higher roughness of Resilience Orthodontic bonding solutions at the nano level is probably enabled by a bigger number of thorns that penetrate into micro concaves formed under the influence of acids. Higher roughness is a consequence of chemical structure itself of the composite material.

 

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Improvement in Public Administration Services: a Case of Business Registration Process

Roy Andersson, Eduardo Bridi, Yinef Pardillo Baez, Mauricio Uriona Maldonadom, Fernando Antonio Forcellini, Fabio Cesar Moraes

This work addresses the process of opening enterprises (grant of license) in a municipality. The purpose is to perform the identification, analysis and redesign of the process of granting permits to private companies, then making a proposal for improvement. The chosen method was a case study, using a qualitative approach according to the BPM methodology to respond: how to improve and accelerate the grant of a license? As a result, the proposed model used the best practices for business registration to reduce the time to 70%, and using half of the involved sectors. The conclusion is that it is possible to reduce

 

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A Methodological Approach to Dematerialization of Business Processes Using Open-Source Technology

Liliana Ávila, Leonor Teixeira, Pedro Almeida

Projects of dematerialization of business processes allow organizations to modernize their administrative activities through the rationalization and optimization of information flows and elimination of documents circulating in paper format. In this article is proposed a methodology for the implementation of projects of dematerialization of business processes in public and private organizations constituted by four stages: preliminary studies and requirements elicitation, modelling, construction and transition. It is also described a pilot-experience in a public entity using an open-source software (Bonita Open Solution) in order to validate the proposed methodology and confirm open-source technologies as a good option to implement this type of projects in a low-cost approach. Furthermore, throughout the paper, some guidelines are provided based on critical success factors and tools to support development stages.

 

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Minimizing and Balancing Ergonomic Risk of Workers of an Assembly Line by Job Rotation: a MINLP Model

Salvatore Digiesi, Francesco Facchini, Giorgio Mossa, Giovanni Mummolo

In today's economic context the workforce is a crucial asset in manufacturing industries. The employee performance and productivity are affected by many factors related on one hand to the line efficiency and, on the other hand, to the well-being of the workers. On the basis of new technologies and driven by Industry 4.0 paradigms, the need of a high production rate cannot neglect the safeguarding of the workers. In case of repetitive manual tasks, workers are exposed to the risk of musculoskeletal disorders (MSDs), that can be reduced by applying ergonomics principles both in design (e.g. workstation design, equipment tools identification, etc.) and in operative phases (e.g. workload balance, tasks assignment, etc.). In the operative phase, job rotation is one of the most widespread methods for alleviating physical fatigue and reducing the stress due to repetitive tasks. However, often, job rotation strategies fail due to the lack of systematic approach or effective management of rotation schedules, being very difficult to identify an effective job rotation schedule allowing maintaining the same productivity rate. The problem is of particular interest under the perspective of the workforce aging, a social European phenomenon which is also affecting production systems performance. Designing and scheduling of human-based assembly systems require a joint evaluation of production system performance and a good balancing of MSDs risk among workers. The authors proposed a model for minimizing the exposure risk of workers involved in repetitive manual tasks, by balancing the human workloads and reducing the ergonomic risk within acceptable limits, for a given production target. Risk and its acceptability are evaluated using the RULA method, according to a mixed integer programming approach. Results shown the effectiveness of the model to identify the optimal job rotation schedules jointly achieving productivity and ergonomic risk goals.

 

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Human Capital Investment: Practices and Measurement In Slovak Enterprises

Iveta Korobaničová, Nicoletta Kováčová

The issue of human capital in the present-day industrially and technologically driven society is becoming an increasingly hot topic. For enterprises in Slovakia thus it presents a challenge to respond to the current trends such as gradual robotization that will lead to the replacement of less qualified jobs by technology in the nearest years. For these reasons also, countries, enterprises or individuals must invest more in the development of human capital but at the same time take into account the return on this investment from the enterprises‘ perspective. The purpose of this paper is to find out how and how much time enterprises in Slovakia devote to the issue of the relationship between the development of human resources and investment in human capital. We also aim to explore whether enterprises assess this investment in human capital at all and in which way they do it. In this paper, we used quantitative research, namely a questionnaire method, which showed that enterprises in Slovakia do not largely invest in the development of their employees. Most companies invest in the development of employees by providing work-related training courses or by offering lectures, workshops and seminars. The results suggest that enterprises most frequently calculate remuneration costs and annual staffing costs that can be considered as traditional methods which, however, represent employees as companies‘ human resources being their liability not an asset they need to develop and invest into.

 

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Social Networks as New Business Concept for Enterprises

Jelena Raut, Slavica Mitrović, Boban Melović, Teodora Lolić

Social networks provide an excellent opportunity for internet advertising and promotion in order to improve business operations. The aim of this paper is to demonstrate the possibility of adequate use of social networks for the establishment, expansion and quality functioning of companies in the area of online trading. Subsequently, the paper presents a concept, a PHP-based web application, used by large trading systems, which is designed and adapted for use in small companies in their everyday operation. Finally, all measures for improving the existing system are presented using a specific case study, through integration with systems owned by company's permanent suppliers, in order to save time and increase the accuracy of procurement, which takes place on a weekly basis.

 

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Knowledge Analysis on Logistics Cost Trade-Offs: a Study With Portuguese Food Sector’ Professionals

Ana Luiza Cordeiro Pereira, Alexandra Manuela Novais Almeida dos Santos Martins, Renata Veloso Santos Policarpo, Maria Teresa Ribeiro Pereira

Logistics is an important area in the economic-financial performance of companies, which makes it necessary to analyse their costs, as well as the trade-offs between them. Thus, the present study, with the objective of analysing the Portuguese food sector logistic professionals’ knowledge regarding to logistics costs trade-offs and their impact on the economic-financial performance of the organizations, showed that there are gaps concerning this subject. Throughout the structured interview and by using the SPSS software, the study shows the existence of flaws in the practical application of the trade-offs’ theory, such as the pressure from the managers for individual cuts in costs; and points out trade-offs of logistical costs relevant to the food sector. These results contribute to the expansion of studies on the subject, besides providing a perspective of the compensatory exchanges that can contribute to the decision making in relation to the costs concerning logistics activities.

 

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Tool Condition Monitoring System Based on a Texture Descriptors

Aco Antić, Milan Zeljković, Nicolae Ungureanu, Ivan Kuric

All state-of-the-art Tool condition Monitoring systems (TCM), especially those that use vibration sensors, in the tool wear recognition task, heavily depend on the choice of descriptors that contain information concerning the tool wear state, which are extracted from the particular sensor signals. All other post-processing techniques do not manage to increase the recognition precision if those descriptors are not discriminative enough. In this work, we propose toll wear monitoring strategy, which relies on the novel texture based descriptors. We consider the module of the Short Term Discrete Furrier Transform (STDFT) spectra obtained from the particular vibration sensors signal utterance, as the 2D textured image. This is done by identifying the time scale of STDFT as the first dimension, and the frequency scale as the second dimension of the particular textured image. The obtained textured image is then divided into particular 2D texture patches, covering part of the frequency range of interest. After applying the appropriate filter bank, for each predefined frequency band 2D textons are extracted. From those, for each band of interest, by averaging in time, we extract information regarding the Probability Density Function (PDF) of those textons in the form of lower order moments, thus obtaining the robust tool wear state descriptors. We validate the proposed features by the experiments conducted on the real TCM system, obtaining the high recognition accuracy.

 

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Solution Space Development: Conceptual Reflections and Development of the Parameter Space Matrix as Planning Tool for Geometry-based Solution Spaces

Paul Christoph Gembarski, Roland Lachmayer

Today’s CAD-systems offer the possibility to model geometry-based solution spaces based on parametrics and feature technology. Here, the solution space is the set of all feasible product alternatives from which a distinct variant for a defined set of requirements may be configured. A necessary step prior to modelling the solution space is to acquire knowledge about dependencies of requirements, solutions and restrictions that are dictated by the supply chain, e.g. manufacturing restrictions. In this article, the authors contribute to this field by developing the Parameter Space Matrix (ParSM) as a tool for a structured elicitation of requirements, solution space restrictions and the resulting model parameters for the CAD-model. Furthermore, the application of ParSM is shown and discussed on a toaster with variable body elements where the manufacturing restrictions result of an additive manufacturing process.

 

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Challenges of Total Customer Experience (TCX): Measurement beyond Touchpoints

Christos G. Chatzopoulos, Marcel Weber

Customer Experience (CX) is an already known term and is usually measured at one or more “touchpoints”, which are direct and indirect interactions between a customer and a company. Most companies typically use touchpoint measurements as a representation for the Total Customer Experience (TCX). However, one can argue that this representation is inadequate since CX is also determined by what is experienced before, between and after touchpoints, which defines the whole customer journey. This paper discusses the adequacy of TCX measured only through touchpoints and investigates the challenges of (a) defining, (b) modelling and measuring, and (c) managing and improving TCX. First, TCX definition challenges are discussed and a new definition of TCX is proposed, considering the four phases that characterise the whole customer journey that are Initiation, Touchpoints, In-between Touchpoints and Finalization. Second, the challenges of modelling and measuring TCX are addressed and a new TCX model that measures emotions is proposed and explained through a fictitious case example. Third, three challenges for managing and improving TCX are discussed and a new way to manage and improve the TCX performance in a company is presented and applied by using the developed TCX model and the case example.

 

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