Periodicals of Engineering and Natural Sciences (PEN - International University of Sarajevo)
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Harvesting Feasibility of Rain Water in Buildings
Get PDFNowadays, population is rapidly growing especially in urban areas and sufficient water supply and harvesting has changed to an urgent and important challenge to develop equal access to water and social needs. The main reasons of lack of water concern in most areas of the world are increased population, environmental pollution, costs and uncontrolled consumption of water, climate changes since the water is consumed in the cycle without return and completion although water is a renewable source. Various new technologies are developed to overcome such a problem in alternative sources for water. Rain water is of great importance due to its quality, purity, PH amount, its content salt and minerals. However, due to lower quality and insufficiency of ground and gray water, rainwater it becomes more important. Present research paper investigates water harvesting feasibility in different countries of the world through considering structures in the underlying study areas. Then an approach was presented as a solution for designers and users with design criteria for the use of rain and gray water in the field of construction. In this approach, the case structure is discussed. Rain waters and gray waters usage sufficiency are discussed in this study according to the sample buildings’ position in the world
Analysis of the EDoS Attack impact on Elastic Cloud Services Using Finite Queuing Model
Get PDFThis paper proposes a logical model to examine the effect of the EDoS attack in cloud environment using finite queuing model and enhanced with experimental model. Due to this sophisticated attacks the computing resources are busy and buffer capacity of the cloud gets exhausted by both the legitimate and malicious user requests, because of this both types of requests could not get the service. The legitimate customers are unable to get service of web application. In this backdrop this paper investigates and evaluates the vendor loss factor from the cost factor of view since the legitimate client requests are denied service. The objective of this analysis is twofold i) to identify the dynamics of the EDoS attacks with different attack rates and to measure the various performance metrics (total number of busy virtual machines, utilization of the cloud resources, request response time, request loss probability, and throughput). ii) The cost function is defined and evaluated based on these performance metrics. Finally compared analytical and experimental results are presented and conclusions are drawn
An Efficient Convolutional Neural Network Based Classifier to Predict Tamil Writer
Get PDFIdentification of Tamil handwritten calligraphies at different levels such as character, word and paragraph is complicated when compared to other western language scripts. None of the existing methods provides efficient Tamil handwriting writer identification (THWI). Also offline Tamil handwritten identification at different levels still offers many motivating challenges to researchers. This paper employs a deep learning algorithm for handwriting image classification. Deep learning has its own dimensions to generate new features from a limited set of training dataset. Convolutional Neural Networks (CNNs) is one of deep, feed-forward artificial neural network is applied to THWI. The dataset collection and classification phase of CNN enables data access and automatic feature generation. Since the number of parameters is significantly reduced, training time to THWI is proportionally reduced. Understandably, the CNNs produced much higher identification rate compared with traditional ANN at different levels of handwriting
GIS risk analysis of a first-degree seismic zone: Kaynaşlı (Turkey)
Get PDFThis study aimed to analyze the land survey maps and existing data to determine the vulnerable areas of the Kaynaşlı districts at risk in terms of natural disaster, as Kaynaşlı is located in a first-degree seismic zone. This three-phase study analyzed geological-geotechnical survey reports via the geographic information system (GIS) and applied them to Kaynaşlı Municipality in Düzce Province (Turkey). First, a non- digital raster suitability map based on a 2005 Kaynaşlı Municipality report was digitized via ArcGIS and used to conduct natural disaster risk analyses of Kaynaşlı. The 2112 buildings covered by the suitability map were then scanned and inventory information generated for each. Finally, using ArcGIS software, the digitized inventory information was superimposed on the suitability map. In Kaynasli, a total 2112 buildings were examined via street screening and their risk status was identified in terms of the terrain. Disaster and risk ratios were calculated and vulnerable areas were pinpointed. All the information obtained from the results of the analyses was shared with the local authorities. According to the physical inventory information, a sustainable data bank was created with the purpose of facilitating the necessary measures for disaster preparedness to be taken by the local authorities in Kaynaşlı. The model of this Kaynaşlı natural disaster risk study could be applied in other communities to assist in identifying vulnerable settlement areas
Design of flexible spot welding cell for Body-In-White (BIW) assembly
Get PDFIn this paper, a flexible spot welding cell - which is flexible both at fixture and work cell level is developed to handle multiple Body-In-White (BIW) part varieties. The work-cell is a human-robot cooperative cell where the operator loads/unloads the parts on one side, whereas the robot concurrently performs welding operation on other side. The fixture is made modular and is reconfigured for change in part varieties. The flexibility of proposed work cell and fixture are investigated and validated by considering two different BIW spot weld assemblies. The performance of robot, cycle time estimation for the process, checking of fixtures, collision detection between weld gun and fixtures are evaluated in virtual environment. The flexible weld cell is proved to be compatible for both the BIW assemblies considered for study. The proposed concept shorten the design & fabrication time of fixture - squeezing the investment cost, assembly cost and floor space; besides reducing the cycle time and improving the robot utilization by 30% - 40% when compared to the conventional method
Operational Stability and Degradation of Organic Solar Cells
Get PDFRecently, Organic solar cells (OSC) have been increasingly utilized all over the world. The changes made in the organic components of the organic solar cells enable them to exhibit good features such as mechanical flexibility, lightness and high power generation efficiency even under lower light intensities. However, operational stability is an important parameter for organic solar cells. Despite the aforementioned advantages of organic solar cells, degradation in operational environments limits their use in harsh conditions. Studies have shown that the organic layer and the cathode layer of the OSCs are degraded by external factors, and this adversely affects the operational stability and productivity of OSCs considerably. The overall efficiency of an organic solar cell is defined as a function of life cycle and efficiency of energy generation. Therefore, the shorter the life cycle becomes, the lesser the overall efficiency of OSCs gets. Recent studies are focused on improving the operational stability and power generation efficiencies of OSCs by reducing the effects degradation induced by external factors, such as climatic conditions and thermal fatigue. The purpose of this study is to assess how organic solar cells work, how they degrade from external factors, such as water and water vapor, and how these parameters affect the operational stability as well as the efficiency of the organic solar cells
Impact of design characteristics of daylight elements to creating healthy internal environment for school buildings evaluation the status of schools in mosul city
Get PDFThis research deals with the impact of design characteristics that create attractive and healthy internal environments for a school building, as one of the most important issues on evaluating the random position of a local school building in Mosul city northern Iraq. The daylight effects factors that support the efficiency of interiors in a school building was discussed in this work, Where, the specific quality of design characteristics related to building components and daylight elements classes were used. The study employed (Velux Daylight Visualizer – 2012) to design the research methodology in order to evaluate three school building types in Mosul city. The gained results of this study confirmed that the design properties related to the factors of daylight have effective role in creating healthy interiors and increase educational productivity. Also, the gained result of this study can be considered as a useful reference for architects, planner, landscape and researchers that they work in Mosul municipality. The objective of this paper is to determine the key design properties affecting to achieve healthy spatial environment, which are related to two main daylight factors. First the solarization average for building at all. Second the homogeneity of daylight at work surface in classroom space
Impact of non-linear electronic circuits and switch of chaotic dynamics
Get PDFSwitch-mode power supply is an extremely non-linear system that can inevitably exhibit unpredictable behavior. These control laws may be insufficient for nonlinear systems because they are not robust when the requirements on the dynamic characteristics of the system are strict [10]. Control laws that are insensitive to parameter variations, disturbances, and nonlinearities must be used. In this paper, we have tested the method of the first harmonic, used to analyses servo controls with a nonlinear element, and to predict certain non-linear behaviors. It mainly allows predicting the limit cycles, but also the jump phenomena, the harmonics as well as the responses of non-linear systems to sinusoidal inputs. We apply this method for the prediction of limit cycles and the determination of their amplitude and frequency. We take as an example a Boost converter controlled by current [4]. This system is chaotic when the duty cycle is more significant than 0.5: we then eliminate the chaos by applying the slippery mode command (for the ripple of the output voltage, for the current ripple of the inductance and switching frequency) when the output is periodic (duty cycle less than or equal to 0.5). In this article, we assess that established approach provides the best outcomes: it appears that the preference between the classical mode and the sliding mode depends heavily on the variance domain of the parameters E, R, and Iref
Modeling of Distributed Generators in 13 Nodes IEEE Test Feeder
Get PDFThis work aims to develop a model capable of evaluating the behavior of distributed energy resources in 13-nodes IEEE systems as a result of the change in the disconnector’s opening protocol that creates a power generation island. The first scenario simulated a failure in the 632-671 line isolating the subsystem into two 375 kVA distributed generation units (DG) in the nodes 675 and 652. Likewise, a second scenario considered the aperture of the disconnector located between nodes 671 and 692 representing a 375 kVA DG feeding a 900 kVA load. The last scenario produced a three-phase failure modeling two 500 kVA DG units in the nodes 634 and 646 supplying an 800 kVA load
Genotyping of human papillomavirus high-risk types and correlation with potential risk factors
Get PDFHuman papillomavirus (HPV) is one of the most common sexually transmitted disease (STD) worldwide. HPV is asmall, double-stranded DNA virus that infects mucosal and coetaneous epithelia trough tiny cuts and abrasion,exposed by the cells of the basal layer. If diagnosed on time HPV can be successfully treated, however, in some casesit can lead to the development of tumor. Most of cervical tumors contain HPV DNA, and majority of them containhigh-risk types HPV16 and HPV18. Different risk factors are associated with HPV infection, including behavioraland biological predispositions. Aim of this study is to genotype potentially infected patients on high-risk types HPVDNA and to correlate the results with patient’s different biological and lifestyle factors. For this purpose 20gynecological smear samples were collected from women, previously subjected to the survey. Methodology includedDNA extraction and real-time polymerase chain reaction (RT-PCR). Results showed that out of 20 patients five werepositive for high risk HPV. Four of five positive patients were positive on HPV16 type of which one had HPV16together with others high risk types. One of five positive patients was positive on HPV18 type and other high risktypes not identified. Final outcome indicates the correlation of potentially endangered patients with specific sexualbehavior and lifestyles, and furthermore represent the general consensus and awareness level this disease has on thepublic.