Optimal Perturbation Iteration Method for Bratu-Type Problems

In this paper, we introduce the new optimal perturbation iteration method based on the perturbation iteration algorithms for the approximate solutions of nonlinear differential equations of many types. The proposed method is illustrated by studying Bratu-type equations. Our results show that only a few terms are required to obtain an approximate solution which is more accurate and efficient than many other methods in the literature.Comment: 11 pages, 3 Figure

Semi-analytical approach for solving a model for HIV infection of CD4+ T-cells

In this work, a mathematical model for the human immunodeficiency virus (HIV) infection of CD4+ T-cells by using the optimal perturbation iteration method (OPIM) is analyzed. Optimization and classical perturbation techniques are combined to build the new proposed method. The iteration algorithm for systems of nonlinear differential equations for this optimal perturbation iteration technique is constructed for the first time. A test problem has been solved and some plots are given to show the reliability and efficiency of the proposed method. Obtained results exhibit the effectiveness and accuracy of the semi-analytical technique.Publisher's Versio

Fostering innovation: Factors that attract and retain third party developers in mobile ecosystems

The popularity of smartphones and the related growth of mobile application markets created a need for mobile platform owners to open their software platforms up to third party developers in order to meet user demand for mobile applications. This external innovation provides a tremendous opportunity for mobile platform owners to develop a volume and diversity of products they could not develop in-house, but it also presents challenges in attracting a sufficient number of developers and users in order to harness the two-sided and same-sided network effects required to successfully cultivate a robust mobile ecosystem. The main objective of this study is to investigate the factors which attract and retain third party developers in mobile ecosystems, a topic about which limited study has been conducted to date. To achieve this goal we developed a research framework based on theoretical and industry literature related to the mobile industry. Using this as a basis for our research we interviewed developers for the iOS, Android and Windows Phone platforms as well as an independent expert specialising in research of the telecommunications industry. These interviews provide a list of factors relating to what motivates third party developers to select a particular ecosystem. Factors are presented in terms of economic considerations, the boundary resources within the mobile platforms, the related development community and the reach the ecosystem provides. These factors are detailed and compared concluding that monetary reward, user engagement and market share are the most dominant factors influencing developer choice. This research complements and extends existing research on third party developer motivation in competitive open innovation communities as well as providing insights into the industry for prospective mobile developers

INVESTIGATION OF BALANCE PERFORMANCES OF COMPETITIVE WOMEN TEAM ATHLETES

In this study, it was aimed to examine the effect of balance-enhancing training applied to competitor women in different team sports. The sample of the study consisted of a total 36 women competitors studying in the Faculty of Sports Sciences and participating in inter-university competitions. The necessary permissions were obtained for the athletes who voluntarily participated in the study, and the consent form was filled in. Athletes who were injured and had any disability were not included in the study. The average age, height and body weight of the athletes are respectively; for handball player (n=12) (21.5±1.49 years, 170.0±2.26 cm, 64.0±2.68 kg); for basketball players (n=12) (20.6±1.47 yıl, 180.3±3.27 cm, 75.8±3.36 kg) and futsal player (n=12) (24.3±1.25 yıl, 177.8±3.05 cm, 73.8±3.36 kg). In the research, pretest and posttest experimental methods were used. The athletes were examined in 3 groups for 8 weeks, 2 days a week, 8 movements of balance-improving training program, and the change in their balance was examined. In the study, the Y Balance Test (YDT) was used before and after the balance-enhancing training program in women handball, futsal and basketball athletes from the team sports, and the arithmetic averages (X) and standard deviations (SD) were recorded in the computer environment before and after the post-test measurements. Descriptive statistics of the volunteers were taken and subjected to normality test. Peer sample and paired sample t test were used to examine the relationships between sports branches, the level of significance within and between the groups was examined at the level of 0.05. The balance training performed for 8 weeks caused positive changes in handball players (p <0.05) but did not caused any change in the basketball and futsal players. As a result, it was found that basketball and futsal players participating in the research had better balance than women's handball players did. Given the importance of balance in asymmetric sports, coaches may be advised to put studies that develop this feature into training programs.  Article visualizations

Foaming behavior of Ti6Al4V particle-added aluminum powder compacts

The foaming behavior of 5 wt.% Ti6Al4V (Ti64) particle (30–200 μm)-added Al powder compacts was investigated in order to assess the particle-addition effects on the foaming behavior. Al compacts without particle addition were also prepared with the same method and foamed. The expansions of Ti64 particle-added compacts were measured to be relatively low at small particle sizes and increased with increasing particle size. At highest particle size range (160–200 μm), particle-added compacts showed expansion behavior similar to that of Al compacts without particle addition, but with lower expansion values. Expansions studies on 30–45 μm size Ti64-added compacts with varying weight percentages showed that the expansion behavior of the compacts became very similar to that of Al compact when the particle content was lower than 2 wt.%. However, Ti64 addition reduced the extent of drainage. Ti64 particles and TiAl3 particles formed during foaming increased the apparent viscosity of the liquid foam and hence reduced the flow of liquid metal from cell walls to plateau borders. The reduced foamability in the compacts with the smaller size Ti64 addition was attributed to the relatively high viscosities, due to the higher cumulative surface area of the particles and higher rate of TiAl3 formation between liquid Al and Ti64 particles.TÜBİTAK for the grant #106M18

Enabling Organizational Agility Through Self-Service Business Intelligence: the case of a digital marketplace

Many organizations have adopted business intelligence and analytics systems in order to cope with the increasing digitalization of data intensive environments. In this paper, we study the role of self-service business intelligence (SSBI), a certain capability provided by a business intelligence system, in enabling organizational agility. In particular, the research question we address is as follows: How does self-service business intelligence enable organizational agility in a multi-sided platform? We focus on two types of organizational agility – namely, market capitalizing agility and operational adjustment agility – and identify how SSBI enables these capabilities in a multi-sided platform environment. We conducted 12 qualitative interviews focusing on Norway’s biggest digital marketplace, Finn.no. Our results indicate that SSBI plays an important role in enabling 1) market capitalizing agility by providing a better understanding of supply and demand participants, more access to traffic data and user clickstreams, fast response to requests, and increased access to supply and demand navigation behavior and 2) operational adjustment agility by redefining current organizational structures, empowering employees, providing equal access to organizational level data and opportunities for data manipulation. The findings provide empirical evidence for the role of SSBI in enabling organizational agility within the context of a multi-sided platform environmen

İkili drinfel’d-sokolov-wilson denklemlerinin modifiyesi ve yaklaşık çözümleri için optimal perturbasyon iterasyon metodu

We try to find the semi-analytical approximate solutions for the system of partial differential equations by using a newly developed scheme. The optimal perturbation iteration method is introduced and then applied to a newly modified coupled Drinfel’d-Sokolov-Wilson equation. Classical perturbation theory and optimization techniques are combined to construct this method. We will deeply analyze an example to prove the power of the proposed method, namely the optimal perturbation iteration method. With the theorem and applications, we see that the present study shows that the new method converges fast to the accurate analytical solutions of the considered equations at even the first two-three iterations.Bu araştırma makalesinde, kısmi diferansiyel denklemler sistemi için yeni geliştirilen bir metot yardımıyla yarı analitik çözümler bulmaya çalışıyoruz. Optimal perturbasyon iterasyon yöntemini tanıtıyor ve sonra yeniden modifiye edilen ikili Drinfel’d-Sokolov-Wilson denklemine uyguluyoruz. Klasik perturbasyon teorisi ve optimizasyon teknikleri birleştirilerek bu yöntemi inşa ediyoruz. Optimal perturbasyon iterasyon olarak önerilen metodun gücünü göstermek için özel bir örneği derinlemesine irdeliyoruz. Teorem ve uygulamalar önerilen tekniğin ele alınan denklemler için iterasyonun daha ilk basamaklarında tam çözüme hızlı bir şekilde yaklaştığını göstermektedir

Efficacy of platelet-rich fibrin matrix on viability of diced cartilage grafts in a rabbit model

Objectives/Hypothesis: The objective of this study was to compare the viability of cartilage grafts embedded in platelet-rich fibrin matrix (PRFM) wrapped with no material (bare diced cartilage grafts), oxidized methylcellulose (Surgicel), or acellular dermal tissue (AlloDerm). Study Design: Experimental study. Methods: In this study, six New Zealand rabbits were used. Cartilage grafts including perichondrium were excised from each ear and diced into 2-mm-by 2-mm pieces. There were four comparison groups: 1) group A, diced cartilage (not wrapped with any material); 2) group B, diced cartilage wrapped with AlloDerm; 3) group C, diced cartilage grafts wrapped with Surgicel; and 4) group D, diced cartilage wrapped with PRFM. Four cartilage grafts were implanted under the skin at the back of each rabbit. All rabbits were sacrificed at the end of 10 weeks. The cartilages were stained with hematoxylin-eosin, Masson’s Trichrome, and Orcein. After that, they were evaluated for the viability of chondrocytes, collagen content, fibrillar structure of matrix, and changes in peripheral tissues. Results: When the viability of chondrocytes, the content of fiber in matrix, and changes in peripheral tissues were compared, the cartilage embedded in the PRFM group was statistically significantly higher than in the other groups (P<0.05). Conclusion: We concluded that PRFM has significant advantages in ensuring the chondrocyte viability of diced cartilage grafts. It is also biocompatible, with relatively lesser inflammation and fibrosis

A New Efficient Technique for Solving Modified Chua's Circuit Model with a New Fractional Operator

Chua's circuit is an electronic circuit that exhibits nonlinear dynamics. In this paper, a new model for Chua's circuit is obtained by transforming the classical model of Chua's circuit into novel forms of various fractional derivatives. The new obtained system is then named fractional Chua's circuit model. The modified system is then analyzed by the optimal perturbation iteration method. Illustrations are given to show the applicability of the algorithms, and effective graphics are sketched for comparison purposes of the newly introduced fractional operatorsThe authors are grateful to the Spanish Government for Grant RTI2018-094336-B-I00 (MCIU/AEI/FEDER, UE) and to the Basque Government for Grant IT1207-1