December 2016


Gorazd Golob






Mechanical properties of 3D printed polymers

Azem Yahamed1, Pavel Ikonomov2, Paul D. Fleming1, Alexandra Pekarovicova1, Peter Gustafson3, Arz Qwam Alden3 and Saif Alrafeek3
1 Department of Chemical and Paper Engineering, Western Michigan University, Kalamazoo, MI 49008
2 Department of Engineering Design Manufacturing and Management Systems, Western Michigan University, Kalamazoo, MI 49008
3 Department of Mechanical Engineering, Western Michigan University, Kalamazoo, MI 49008


Polymeric bone implants are used in many medical applications. To create bone structures from plastics that can match the real bones, the structure and mechanical properties must be tested to make sure they can sustain loads comparable to the original. Also, it is very important to use proper materials that provide biocompatibility. In this work, the mechanical properties of 3D printed samples of thermoplastic materials that can be used for 3D printing of human bone structure substitutes were tested. The thermoplastics that were printed using 3D printing are acrylonitrile butadiene styrene (ABS), Digital ABS™, polylactic acid (PLA), polyetherimide ULTEM 9085 and polyamide PA 2200. The samples of ABS and PLA were printed using fused deposition modeling technology (FDM), Digital ABS™ was printed using PolyJet™ technology, and ULTEM 9085 and PA 2200 were printed using selective laser sintering (SLS). Compression tests showed that PLA and Digital ABS™ create anisotropic 3D printed structures, because they exhibited different stress vs. strain properties in different directions. The samples made from ABS, ULTEM9085 and PA2200 have the same shape of stress-strain curves in different printing directions, but different slopes, which shows that these printed structures are also anisotropic. Differential scanning calorimetry was used to acquire the thermal analysis profile of these polymers. The thermal analysis results of these polymers indicate that ABS and ULTEM9085 are amorphous while PLA is partially crystalline and PA2200 is completely crystalline.

Keywords: polymeric material, fused deposition modeling, bone structure, 3D model, selective laser sintering

JPMTR 088 | 1608 Research paper
DOI 10.14622/JPMTR-1608
UDC 620.1|531-3:678.5

Received: 2016-08-11
Accepted: 2016-12-16

Designed structures for bone replacement

Azem Yahamed1, Pavel Ikonomov2, Paul D. Fleming1, Alexandra Pekarovicova1 and Peter Gustafson3
1 Department of Chemical and Paper Engineering, Western Michigan University, Kalamazoo, MI 49008
2 Department of Engineering Design Manufacturing and Management Systems, Western Michigan University, Kalamazoo, MI 49008
3 Department of Mechanical Engineering, Western Michigan University, Kalamazoo, MI 49008


Bone replacements are needed to help repair or replace damaged and diseased tissues ranging from trauma, degenerative disease, cancer and plastic surgery requirements. To create artificial bone implants from plastics, the structure and mechanical properties must be tested to closely match or be able to sustain greater forces than the original. It is essential to use proper bone replacement material that provides biocompatibility with sufficient stiffness and strength. The materials can be biocompatible polymers, such as polylactic acid (PLA), polyvinyl alcohol (PVA), polycaprolactone (PCL) and polyether-ether ketone (PEEK). Also, it is important to create internal structures that can accurately mimic the real human bone structure with a solid outer shell that represents the compact bone and porous internal volume that represents the trabecular (spongy) bone. Designing of the proper trabecular bone is one of the most critical steps, because its structure helps support the entire bone, while at the same time reduces the weight. Due to the low resolution of DICOM images, the trabecular bone structures cannot be obtained directly from CT and MRI scans. Therefore, we used CAD software – SolidWorks to design special 3D structures (hexagonal, triangular, and square). The reason for using these structures is that they are widely used in industry and aerospace applications, because they provide high strength, while keeping the weight low. The geometry of the void structure reduces the amount of material, reducing the overall weight and cost by reducing the structural density. We designed and produced 3D printed samples to test the structure properties with different geometric shapes. Structure property tests, such as tensile strength test, compressive strength test, and bending test were investigated. We found that the mechanical properties of the designed plastic structures either exceed or fall within the range of the mechanical properties of the human trabecular bones.

Keywords: mechanical property, 3D printing, biomaterial, bone structure

JPMTR 089 | 1614 Research paper
DOI 10.14622/JPMTR-1614
UDC 620-024-035.56

Received: 2016-11-08
Accepted: 2016-12-27

Gender stereotype and advertisement language on newspaper and magazine media platform in Nigeria

Ojinga Gideon Omiunu
Unicorn Academics and Organisation Developmental Research Centre, Ibadan, Nigeria, P.O. Box 20671, UI Post office, Ibadan, Oyo State, Nigeria;


This study seeks to investigate gender stereotype and the language of advertising used in media platform in Nigeria. A convenient sampling was deployed to select three indigenous newspapers and two magazines in Nigeria. The three newspapers used for this study are the Tribune, Guardian and the Nation; and the two magazines used are Ovation and City people. The findings of the study revealed that gender bias occurs in media advertisement in Nigeria and it is more pronounced in newspaper than in the magazines. Body images of females in advertisement were more exposed that those of male and the most revealed female body parts were the arms, thigh and chest, among others, while for the males only their arms and legs were revealed. The majority of advertisement done in newspaper and magazines are gender specific, that is, they addressed particular and specific gender type thus neglecting the other gender type. The study recommends that the female gender should not be portrayed in the society as mere sex objects. Also, advertising agencies should endeavor to make advertisements to be gender neutral; however, it is also important to put into cognizance the particular gender for which the advertisement is produced.

Keywords: advertising model, gender differences, human body, image, media market

JPMTR 090 | 1613 Case study
DOI 10.14622/JPMTR-1613
UDC 659.1:070-055.1/3

Received: 2016-10-07
Accepted: 2016-12-27

Mental model of a medieval scribe as a basic engine concept for an intelligent, bibliophilic book design system

Bogdan Szczurek1 and Tadeusz Szuba2
1 Ruthenus Publishing House, Krosno, Poland
2 AGH University, Dept. of Applied Computer Science, Krakow, Poland


This paper presents the current state of the research project which aims to build a mental model of an abstract medieval scribe. It will be the basis for the design of a novel intelligent engine for a book design system enabling to easily create books of exceptional artistic and bibliophilic value. A page of a book filled with illustrations, ornaments and text can be considered as an extension of the idea of a Turing Machine infinite tape. From this point of view, a mental model of a scribe can be considered as an extension of Alan Turing’s concept of an abstract clerk-mathematician, processing a tape according to this tape’s contents and the contents of his brain serving as a control module. Thus, authors want to expand the concept of the Turing Machine to design a model of an abstract medieval scribe and to use it as a basis for a future desktop publishing system. Joint knowledge of the authors on the practice of bibliophilic book edition and on the theory of artificial intelligence and expert systems provides a real chance that this project will be completed and implemented. This paper presents the basic theoretical foundations of the project.

Keywords: Turing Machine, clerk versus scribe, artificial intelligence, editing system, design system

JPMTR 091 | 1607 Research paper
DOI 10.14622/JPMTR-1607
UDC 159.925|81’04:090.1

Received: 2016-05-04
Accepted: 2016-12-13