Applying Simulation Modelling in Quantifying Optimization Results

Improvements achieved by applying linear programming models in solving optimization problems in logistics cannot always be expressed by physically measurable values (dimensions), but in non-dimensional values. Therefore, it may be difficult to present the actual benefits of the improvements to the stake holders of the system being optimized. In this article, a possibility of applying simulation modelling in quantifying results of optimizing cross dock terminal gates allocation is outlined. Optimal solution is obtained on the linear programming model by using MS Excel spreadsheet optimizer, while the results are quantified on the simulation model, by using Rockwell Automation simulation software. Input data are collected from a freight forwarding company in Zagreb, specialized in groupage transport (Less Than Truckload - LTL).

Testing the Force Absorption of Composite Materials to Select the Best for Making a Helmet

The paper presents and describes the procedure of testing the materials that were available for the production of a multifunctional protective helmet. The procedure was carried out at the company Šestan-Busch d.o.o. as part of the EU project for the development and production of a multifunctional protective helmet. The test results showed that carbon fibers polymers as a composite material have the best impact absorption properties which was a key criterion for material selection. Other materials; glass fibers polymers, aramid fibers polymers and combinations in the test procedure showed worse results compared to the selected criterion.

Suitability of Recycled PLA Filament Application in Fused Filament Fabrication Process

Fused filament fabrication (FFF) is currently one of the most popular additive manufacturing processes due to its simplicity and low running and material costs. Support structures, which are necessary for overhanging surfaces during production, in most cases need to be manually removed and as such, they become waste material. In this paper, experimental approach is utilised in order to assess suitability of recycling support structures into recycled filament for FFF process. Mechanical properties of standardized specimens made from recycled polylactic acid (PLA) filament as well as influence of layer height and infill density on those properties were investigated. Optimal printing parameters for recycled PLA filaments are determined with Design of Experiment methods (DOE).

Six Sigma Approach to Enhance Concurrency of the Procurement Process for Raw Materials

This paper presents the improvement of the procurement process for raw materials in a real manufacturing company supported by the Lean Sig Sigma as structured approach to deliver the improvement. The manufacturing company that is a subject of this paper have received a significant amount of complains regarding the internal purchase orders approval process and the overall procurement process of the company from both internal employees and external vendors and contractors. Considering that the company is procuring the raw goods from selected vendors, therefore the entire manufacturing plan depends on these materials, the company decided to improve this process trough Lean Six Sigma. The Lean Six Sigma approach was selected in order to obtain the improvement in a short time, based on indicators that were previously analyzed and prioritized. The paper focuses on simplifying of the process trough decreasing the number of mandatory steps.

ATLaS: Assistant Software for Life Scientists to Use in Calculations of Buffer Solutions

Many solutions such as percentage, molar and buffer solutions are used in all experiments conducted in life science laboratories. Although the preparation of the solutions is not difficult, miscalculations that can be made during intensive laboratory work negatively affect the experimental results. In order for the experiments to work correctly, the solutions must be prepared completely correctly. In this project, a software, ATLaS (Assistant Toolkit for Laboratory Solutions), has been developed to eliminate solution errors arising from calculations. Python programming language was used in the development of ATLaS. Tkinter and Pandas libraries were used in the program. ATLaS contains five main modules (1) Percent Solutions, (2) Molar Solutions, (3) Acid-Base Solutions, (4) Buffer Solutions and (5) Unit Converter. Main modules have sub-functions within themselves. With PyInstaller, the software was converted into a stand-alone executable file. The source code of ATLaS is available at https://github.com/cugur1978/ATLaS.

Exploring Successful Small Urban Spaces’ Criteria with Emphasis on Cultural Context

In the crowded cities of the present age, public spaces can provide a quiet area away from the hustle and bustle of the city that citizens can interact with by incorporating utility features and meeting human needs and Relax there. Small urban spaces are among the most important and effective urban spaces to achieve this goal. Because these spaces due to their small size and lower costs (compared to larger spaces) for construction can be created in large numbers and distributed throughout the city. In this way, citizens will be able to reach a public urban space on foot in a short time. If these spaces are well designed, they can encourage people to stay in and interact with each other. It is not difficult to identify and experience high-quality successful places, but identifying the reasons for their success is difficult and even more difficult, understanding if similar spaces in other places can be considered successful. This question is important because public space with deep social content is considered a cultural product. Public space is the product of the historical and socio-cultural forces of society. Therefore, one of the most important issues that should be considered in the study of public spaces and the reasons for their success is the cultural context. In Iranian cities that have been influenced by the values and principles of Islam,recognizing Islamic principles and their role in shaping public spaces can lead us to desirable results. The purpose of this article is to develop a conceptual model of successful small urban spaces with an emphasis on cultural issues, especially in Iranian-Islamic cities. In this regard, the effective criteria for the success of urban spaces in general and small urban spaces in particular in the two categories of Western countries and Iranian Islamic cities were examined and then, taking into account the criteria derived from cultural theorists, the conceptual model of research with 38 subcriteria is provided.

Comparative Study on the In-Ladle Treatment Techniques for Nodulizing the Iron’s Graphite

The objectives of this research is to study and understand the nodulizing of ductile iron using in-ladle treatment process. Among the more common nodulizing agents is magnesium (Mg) which is conventionally added to the cast iron by combining suitable alloys of one or both of these elements with molten cast iron. Depending on the characteristics of each master alloy used as nodulizer, different treatment methods and techniques are used, among these, the most widely used being in-ladle, in-mould, and flow-through, the first being the most used. This research deals with the parameters, that affect the quality of ductile iron produced using in-ladle treatment process. The parameters involved are the percentage of magnesium–ferrosilicon (Fe–Si–Mg) used and the nodulizing technique. In-ladle treatment used consists of a deep pocket into the bottom of ladle, in which magnesium–ferrosilicon is placed into it together with a steel scrap barrier (steel sheets) or calcium carbide. This study, take into account, the degree of assimilation of magnesium, which shows the performance of the chosen process, depending on the nodulizer used and the temperature of the treatment.

Technical Aspects of Web Photography as a Medium of Tourism Development

Information and communication technology is an important factor for national, regional and local sustainable tourism development according to the long-term Croatian national strategic plan. New forms of information, such as web sites; new media, materials, political and social change, all influence tourists’ decisions when choosing specific destinations. The aim of this research is to determine, based on the analysis of the tourism media campaign, the relationship between new communication trends and the application of photography as a medium that influences the experience when choosing a destination and the importance of crucial information factors on web pages based on their technical and visual characteristics.

Sensors and Their Application in Precision Agriculture

The paper depicts sensors in precision agriculture. It encompasses the most significant and frequently used sensors in agriculture. Furthermore, the paper explains the main sensor types according to their design, the recorded range of electromagnetic spectrum, as well as the way of detection, recording, measuring, and representation of the detected energy. The development of remote research has provided deeper understanding of remote sensors and their advantages. The sensors installed on soil testing equipment, fertilizing and crop protection machinery, as well as crop picking machinery have been analyzed relative to precision farming. The paper depicts widely known sensors OptRx, ISARIA and VRT technology. The results of the paper assess the data collected by sensors and processed in order to produce maps for agrotechnical operations. The application of maps decreases the employment of human resources, heightens the capacity of data collection, increases the precision of agricultural activities, and finally results in decreasing the cost of final products. The technological progress over the past decade has enabled the development of technology with variable application standards (VRT) that, according to current needs, enables input optimization.

A New "Intersection" Method for Multi-Objective Optimization in Material Selection

Till now the previous methods for multi-objective optimization adopt the "additive" algorithm for the normalized evaluation indexes, which has the inherent shortcoming of taking the form of "union" in the viewpoint of set theory. In fact, "simultaneous optimization of multiple indexes" should be more appropriate to take the form of "intersection" for the normalized evaluation indexes in the respects of set theory and "joint probability" in probability theory. In this paper, a new concept of favorable probability is proposed to reflect the favorable degree of the candidate material in the selection; All material property indicators are divided into beneficial or unbeneficial types to the material selection; Each material property indicator correlates to a partial favorable probability quantitatively, and the total favorable probability of a candidate material is the product of all partial favorable probabilities in the viewpoints of "intersection" of set theory and "joint probability" in probability theory, which is the sole decisive index in the competitive selection process. Results of the application examples indicate the validity of the new method.