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Unmanned Surface Vehicles in Maritime Critical Infrastructure Protection Applications — LNG Terminal in Świnoujście

Abstract

In order to first Baltic LNG terminal in Świnoujście construction, issues concerning maritime critical infrastructure protection as a part of Maritime Security appeared. With the increasing natural gas demand LNG terminal in Świnoujście could be a possible terrorist attack target as well as the LNG carriers crossing the choke point of Baltic Straits and sailing through the littoral waters of Polish and other Baltic counties coastline. Experts do not fully agree on possible effects and results of successful terrorist assault on LNG carrier at sea nor at harbor.

Unmanned platforms begin to play prominent role in military, oceanography or academic applications. With the announcement of reducing the hazard for deck operators especially in high-risk regions, it is predicted that unmanned platforms will play crucial role in Maritime Security systems in the nearest future. This paper discusses the design of the USV dedicated to LNG terminal protection tasks introduces potential equipment options and missions scenarios of first Polish unmanned platform ‘Edredon’.

Open access
Air Exchange Rate in Air Quality Assurance – A Case Study

Abstract

The goals of this paper are to estimate some parameters – indoor temperature and ventilation rate - necessary to determine the heat load demand for ventilation in the amphitheatre named ‘A TALPOSI’-Faculty of Buildings Engineering- with a number of at the most 120 occupants. The study presented in this paper is made when in the amphitheatre it is necessary to assure a comfortable temperature by a permanent functioning of the heating system. The number of air exchanges necessary in the amphitheatre in the natural ventilation process, more exactly, to assure a minimum air exchanges, is imposed by the requirements for the assurance of physiologic comfort in the amphitheatre for the time interval when it is occupied by students. The inner air debit should cover the harmful emissions in the amphitheatre. By the help of these calculated (measured) parameters we have calculated the heat load for ventilation. In the end, with the data obtained from calculations and measurements we find ourselves in the situation of establishing the size of the heat exchanger corresponding to the room, to heat the fresh air taken from outside and send it inside the amphitheatre. The measurements are made with the TESTO apparatus of the faculty. The minimum requirements to assure the thermal comfort are: to achieve a minimum internal temperature θi (t) higher than (or equal to) the normal indoor temperature associated to this space and to assure the air quality, the air exchange rate. The authors want to highlight by this study the necessity and importance of the control on the number of air exchanges in rooms with a high number of occupants and overall, the control of the fresh air debits. The fact that the focus is more and more on heat loss cuts in rooms by tightening closing elements gives birth to the necessity of control of the ventilation system with effects on the consumption of mechanical energy.

Open access
Control and Optimization Against Earthquake by Using Genetic Algorithm

Abstract

In this paper, controlling and optimizing against the earthquake by using genetic algorithm is investigated. In this paper, a new approach for selecting optimal accelerograph and scaling them for dynamic time history analysis is presented by the binary genetic algorithm and natural numbers, in order to achieve the mean response spectrum, which has a proper matching and a short distance with the target spectrum and indicates the expected earthquake of the site. Because of the difference in the nature of accelerograph and the scale coefficients, the genetic algorithm presented in this paper, is hybrid (has two chromosomes). The proposed algorithm is capable of constructing a new generation of people from a series of infinitesimal earth movement records, in a process where natural selection, mating, mutation takes place, and creates a new generation of people and continues this process until a person with desirable qualities is obtained. One of the most important factors in the accuracy and efficiency of these programs is the correct estimation of their parameters. If these parameters are correctly calculated, the difference between the mean response spectrum and the spectrum of the plot will be greatly reduced. Due to the relatively large number of these parameters, the use of trial and error-based methods largely relies on user skills, the proposed hybrid genetic algorithm program can overcome this defect. The program has two genomes that run simultaneously and provide close answers to the optimal answer. The program itself is able to provide the user with a range of optimal coefficients and crossing values and mutations of each chromosome.

Open access
Experimental Evaluation of the Effect of Silica Fume on Compressive, Tensile Strength, Abrasion Resistance, Slump and Impact Test and Water Permability Coefficient of Concrete

Abstract

The use of various additives (admixtures) in concrete and cement products has been considered by various researchers in recent years. Microsilica (Silica fume) can also be considered as one of the most widely used additives (admixtures) in this section. In this study, 120 concrete specimens were constructed using a mix design based on ACI in the laboratory with an overview of records and advantages of using microsilica in concrete. The microsilica used in concrete specimens has been considered 2%, 5.5% and 7.5% by weight of cement. Finally impact permeability, tension and uniaxial compressive strength tests were done on concrete specimens and their mechanical properties were evaluated. The results show that microsilica improves the mechanical properties of concrete. The results also show that the use of microsilica in ordinary concrete has a very positive effect in controlling the surface cracks and increasing some strength parameters such as tensile and compressive strength of concrete.

Open access
The Impact of Carbon Dioxide Concentration on the Human Health - Case Study

Abstract

From various other studies, it is known that the maximum carbon dioxide concentration in different countries is between 1,000 ppm up to 1,500 ppm. Therefore, the research is focused on indoor environment, namely the production of pollutants from the persons inside office rooms. The article presents the trend of the carbon dioxide concentration from the occupants inside an office. It is examined the carbon dioxide production separately for men and women, for persons of different mass and for persons of different ages. It is also analyzed the carbon dioxide production during a sedentary and physical activities. In parallel with the production of carbon dioxide is presented the monitoring of the human pulse and blood pressure. All these parameters are monitored together with relative humidity and indoor air temperature. The aims of this paper is to describe the partial results of human respiration impact on indoor air quality in closed spaces and to research the connection between carbon dioxide concentration and human health.

Open access
Investigating the Effect of Distance and Diameter Ratio of Elliptical Piles on the Amount of Force Exerted by Waves in the Pile Groups with Regular Layout

Abstract

Today, advanced countries compete enormously for further exploitation in the offshore area, for its enormous fresh resources and space. Therefore, these competitions will double the importance of these types of structures. As it is known, the most important part in the design of the offshore structures is the design of the piles on which the structure will be placed. Engineers have always been trying to build these types of structures with the least cost and the highest safety factor. In this research, the effect of distance and the ratio of the elliptical pile diameters on the strength of the pile group was evaluated using numerical modeling. Five different states of diameter ratios including: 1.2, 1.4, 2, 2.5, 3 and five different distance ratios were investigated. The results demonstrate that with the increase in the diameter ratio, the amount of force decreases while it increases as the distance ratio rises.

Open access
Lifetime Glass Reinforced Plastic Pipes by Measuring the Stiffness

Abstract

The lifetime of glass reinforced plastic pipes is 50 years. Extensive use of this type of pipe in its various applications, led to investigate their behavior in land that anthropogenic or natural causes, shows the different values of pH to neutral. The paper presents experimental results conducted on three samples of a PN SN10000 DN150 PN10 pipe buried in three different types of terrain: neutral, acidic, basic. They were subjected to axial load, measuring the force applied deformation force function. On the basis of the calculation formulas determined rigidity of the pipeline, the deformation speed of 50 mm / min. This concludes the type of land affects the rigidity of the pipe so its length of life decreases to that provided by suppliers in order to be taken compensatory measures in this regard such as choosing a higher class of pressure and stiffness pipeline than those arising discounted. This will allow for long-term value (50 years) in the mechanical characteristics sufficient for safe operation.

Open access
Performance of Concrete by Using Albumen, Yolk and Milk

Abstract

In ancient structures such as Jabalieh dome at Kerman and Dokhtar Bridge at Mianeh in Iran, it was said that egg and in some cases egg and camel milk were used in the mortar. Thus, it was imagined that the stability of these structures were based on these traditional materials. Therefore egg parts and also camel milk were used as a portion of water in the concrete to evaluate this traditional theory. For this purpose, 16 concrete mix designs included 144 cubes, 16 cylinders and 16 prisms were casted. Various percentages of albumen, yolk or camel milk were used. Results showed that by substituting 0.5% of water content with albumen, compressive strength was similar to control specimen. But splitting tensile strength and three-point flexural strength were 7.2% and 18.9% higher than control specimen, respectively. Moreover, because of camel milk’s fat, usage of this material was not suggested.

Open access
Ranking of Effects of Construction Delay: Evidence from Malaysian Building Projects

Abstract

The problem of delay is a regular phenomenon in construction projects all around the world and the Malaysian building projects has no exclusion. The aim of this paper is to determine and rank the effects of delay in Malaysian building projects with respect to their Relative Importance Index. Literature review and questionnaire survey were used to gather data for this study. A thorough literature review was performed to identify the common effects of delays in building construction projects. A questionnaire was distributed among key project participants; contractors, clients and consultants, to rank the effects of delay in Malaysian building projects based on the perception of survey respondents. In total 300 questionnaires were distributed, as a result of 240 questionnaires were received. The collected data of questionnaire survey was analysed using statistical software SPSS. In total, 17 effects of the delays have been determined and findings from the survey revealed that time overrun, cost overrun, dispute, loss of profit, arbitration, claims, contract termination, litigation, poor quality of work, and total project abandonment were the main effects of delay in Malaysian building projects. The findings of this study might encourage construction stakeholders to focus on the issue of delays in building projects.

Open access
A Study of Groundwater Characteristics by Using of Groundwater Quality Index and Pollution Index in Zubair District, Basra Province, Iraq

Abstract

The present work evaluated the groundwater quality index (GWQI) depending on some physicochemical analyses of thirteen groundwater samples in the Zubair district in Basra Province, Iraq. The collected groundwater samples were subjected to an extensive physicochemical analysis to evaluate the characteristics of water for drinking purpose according to Iraqi standard. For calculating the (GWQI), twelve water quality parameters were considered; turbidity, pH, chloride, total dissolved solids, total hardness (TH), electrical conductivity (EC), sodium, sulphate, phosphate, calcium, nitrate, and magnesium. The analysis of the results reveals that all the samples surpassed the portability of drinking water limits. High values of the (GWQI) in the obtained groundwater samples could possibly be caused by the higher values of electrical conductivity, total hardness, chloride, total dissolved solids and sodium within the groundwater. The calculated GWQI values ranged from 73.36 to 595.92. The pollution index (PI) was calculated for the study area with values ranged from 2.97 to 8.26. Correlation coefficients amongst the chosen water parameters exhibited some strong relationships. Finally, the analysis shows that the groundwater in this particular area needs to be treated before its consumption, and in addition, it usually needs to avoid the hazard of contamination. Principal component analysis (PCA) and cluster analysis (CA) indicate that the acquiring-data from groundwater samples are explained 90.5 % of the variance in the data with a four-component system that explains a large portion of the total variance of collected data.

Open access