Periodicals of Engineering and Natural Sciences (PEN - International University of Sarajevo)
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A Review on the Matrix Toughness of Thermoplastic Materials
No full textComposite material has attracted increasingly remarked interest over the last few decades and set it apart in itsown class due to its distinct properties. This paper is a review on the matrix toughness of thermoplastic polymercomposites. Toughness of thermoplastics has been actively studied since the 1980s.the main advantage in usingthermoplastics to toughen resins is that their incorporation need not result in important decreases in desirableproperties such as modules and yield strengths. However, the predominant criteria for achieving optimumtoughness enhancement in the thermoplastic toughening of epoxy resins are still not all that clear from theliterature. Epoxy and polyester resins are commonly modified by introducing carboxyl-terminated butadieneacrylonitrile copolymers (ctbn). A tough elastomeric phase, for example, a silicone rubber with good thermalresistance in a polyimide resin, produced a tough matrix material. It summarizes what the authors believe are theimportant requirements for good thermoplastic toughening. 
Economic and environmental performances in manufacturing industries: A comparative study
Get PDFThe paper empirically investigates the dynamic relationships between economic and environmental performances in manufacturing industries on a comparative basis in India and China. The economic performance is generally measured by production and export. Manufacturing sector plays a crucial role in terms of GDP and export both in India and China due to existence of their emerging markets. The rapid export-led economic growth with remarkable contributions of manufacturing industries in India and China also raise the question of their environmental performances nowadays. In this context, environmental effect of manufacturing performances measured by the CO2 emission is a serious concern for both countries. The study is conducted within a causality framework by using World Bank data on Indian and Chinese economy from 1970 to 2016. Several unit root tests are conducted for all time series variables before applying the Johansen co-integration test followed by vector auto regression models to find their causal relationships. Findings show a unidirectional causal linkage between manufacturing production and CO2 emissions in both countries, the degree of the effect of manufacturing sector on CO2 emissions is remarkably higher in China than in India. Manufacturing export is also found as a significant factor in high level of CO2 emissions in China
Testing the random walk hypothesis of stock indexes through variance-ratio
Get PDFThe Random Walk is considered to be a tool trying to explain the characteristic of movement of prices in the financial markets. It can also be seen in the form of a trial to demonstrate the non-predictability of future changes in the financial markets through reliance on the characteristics identified based on past price changes. In this paper used is the variance-ratio test initiated by Lo and MacKinlay to test the Random Walk Hypothesis for a more recent data of eleven Stock Indexes, seen as main indexes of the current marke
The UAV Control Approach by using Multi Agent Systems
Get PDFThe Unmanned Aerial Vehicles (UAV) are becoming more and more accessible and their applications will grow with various utility’s from military fields with specific missions to civil so that in-depth research, in which all this types of UAV’s will operate in the future airspace, has to be done via a new concept on systems centralized autonomous control system. Approach of a Multi-Agent System (MAS) used for the development of an autonomous UAV Control System is presented. In the proposed model some processes are simplified, however it is unique, and can be used as it to help UAV’s operate in the flight airspace. This system will serve many UAV users to help them work in the same defined airspace without concerns regarding safety. The proposed model is a new concept of a multi-agent system design, simulated in NetLogo software, which include the parameters necessary to function with the objective to maintaining separation
Research on mechanical design of a multi-function finger rehabilitation robot
Get PDFTraining with robots for injured fingers has achieved the efficacy of treatment. However, most of finger rehabilitation robots just have bending/extending movement. This paper presents a new multi-function finger rehabilitation robot with a simple mechanical structure, which could help fingers and thumb realize bending/extending movement and stretch/adduction movement. The paper firstly analyzes the hand physiological movement mechanism, confirming the motion range of each finger’s joint. Based on the fingers movement rules, the robot driving structure has been developed, which includes thumb training module and fingers training module and frame. In order to prove the rationality of mechanism design, an experiment was conducted. The experiment proved that the mechanism can run smoothly, and its rope wheels also drive well without skidding phenomenon as well as its tension is appropriate
Model for the assessment greenhouse gas emissions from road transport
Get PDFA three-level model for estimating greenhouse gas (GHG) emissions by mobile and stationary road transport facilities of a state or region, proposed in this article, takes account into GHG emissions from a vehicle fleet (mobile objects) and road transport infrastructure (network of car services, road network of various categories).
Additionally, it has been developed the intellectual system which evaluates the reliability of the array of initial data, by increasing the range and adjusting (if necessary) the values of individual indicators, as the result we achieving the convergence of the calculating GHG emissions from motor vehicles according to the models of all three levels of assessment. This ensures verification of the obtained gross GHG emissions.
Evaluation of greenhouse gas emissions using three-level model was carried out for St. Petersburg and the Leningrad Region (Russian Federation), they shown the possibility of reducing by 2030 by 3.2 ... 12.4% of gross GHG emissions by motor transport of the Russian Federation in comparison with 2015. For St. Petersburg and the Leningrad Region, both the reduction of gross GHG emissions by road transport (12.7% innovative scenario) and their growth (4.8% inertial scenario) are expected during the forecast period. At the same time, both for the St. Petersburg and the Leningrad Region and for the state as a whole, a significant reduction in gross GHG emissions by road transport is expected in the period after 2025 due to the intensive replacement of cars on oil fuel by electric vehicles and hybrids, changes in the transport behavior of the population, the development of public passenger transport and cycling, the introduction of autonomous vehicles, etc
Clustering algorithms subjected to K-mean and gaussian mixture model on multidimensional data set
Get PDFThis paper explored the method of clustering. Two main categories of algorithms will be used, namely k-means and Gaussian Mixture Model clustering. We will look at algorithms within thesis categories and what types of problems they solve, as well as what methods could be used to determine the number of clusters. Finally, we will test the algorithms out using sparse multidimensional data acquired from the usage of a video games sales all around the world, we categories the sales in three main standards of high sales, medium sales and low sales, showing that a simple implementation can achieve nontrivial results. The result will be presented in the form of an evaluation of there is potential for online clustering of video games sales. We will also discuss some task specific improvements and which approach is most suitable
Modeling of the processes of increasing foreign economic potential of the microeconomic system
Get PDFThe enterprise as an economic system at the micro level is characterized by uncertainty in situations when making decisions, a large number of input indicators, as well as the presence of a decision maker of information that is poorly formalized and cannot be taken into account when applying only quantitative methods. The uncertainty of the system leads to an increased risk of ineffective decisions, which may result in negative economic, technical and social consequences. The research considers the main structural elements of the strategy of developing the foreign economic potential of microeconomic systems. On the basis of calculations, the clear meaning of the indicators that are included in the groups defining the basic elements of the external economic potential is obtained. The algorithm of forming the strategy of development of the foreign economic potential of the enterprise is presented in the framework of the general approach to the organization of the process of increasing the foreign economic potential of microeconomic systems on the basis of a unified information system. As a result of the formation of a mechanism for increasing the foreign economic potential of microeconomic systems, a strategy was developed that was based on substantiation of the direction of development of foreign economic potential in accordance with the level of influence of external factors, using the method of fuzzy modeling and modeling the process of organizational interaction
Ensuring of the enterprisе operation effacacy: management aspect
Get PDFThe article investigates the approaches to the definition of the category essence "management effacacy". The object of research is the theoretical and methodological enterprisе efficacy composition aspects. The subject is ensuring of enterprisе effective management. The study purpose is to find ways to guarantee the enterprisе efficacy functioning by improving the management, financial and economic security fixed capital system. The following tasks are implemented for this: analysis of publications on the enterprisе efficacy management; definition of principles for the enterprisе efficacy management implementation; improvement of the management system based on the fixed capital efficient use; enterprisе economic security main components determination and implementation levels of environmentally safe technologies for enterprisе efficacy management.
To solve the research problems, the principles of dialectical logic, the unity of logical and theoretical, system analysis, problem-oriented and system-structural approach, classification methods, expert assessments were used.
The article presents a model of internal audit of the core capital of enterprisеs, which reflects organizational, legal, operational and accounting control.
The enterprisе economic security main components and the levels of environmentally safe technologies implementation at enterprisеs are highlighted. Also the main priority interests of the environmentally friendly technologies introduction, which are the main capital for enterprisеs have been determined, and draws up a logical scheme of the levels and stages of management decision-making to ensure the innovative technologies development has been drawn up
A performance Evaluation of Transform Domain Algorithm in Watermarking Based on Different Levels of Sub-Bands of Discrete Wavelet Transform
Get PDFThis study proposed to evaluate the performance of transform domain algorithms in watermarking based on different level of sub bands of discrete wavelet transform (DWT) that can be used to overcome illegal copy, manipulation, distribution and reproduction of image on the network by implementing watermarking algorithm based on different levels that is low-level (LL), low- high (LH), high-low (HL), High-high (HH) and singular value decomposition (SVD) on image for their robustness, and imperceptibility. Moreover, two parameters were applied to evaluate the performance. That is, peak signal to noise ratio (PSNR) is used to measure imperceptibility of the digital image while normalize cross correlation (NCC) is applied to measure the robustness of digital image. The performance evaluations of the proposed method were implemented in MATLAB. The results showed that the described method imperceptible of HL level sub-bands than other levels of sub-bands. While the robustness is achieved by all levels sub-bands