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Optimization of Building Façade to Control Daylight Excessiveness and View to Outside

Abstract

Windows and shading devices play a significant role in designing building facades to control the rate of the received daylight and improve visual comfort. This study is aimed to provide an optimization basis for building’s façade considering two variables of Annual Sun Exposure (ASE (1000/250h)) and the view to outside of an office. In this research, the effect of various parameters of shading louvers to the south was investigated in Tehran, Iran. The parameters were number, depth, angle as well as thickness. In this review, Rhino/Grasshopper plug was employed for simulations; moreover, Galapagos evolutionary solver component was used to run the optimization process. This study’s findings showed that it was possible to reach a view of nearly 90% of the interior spaces while the value of ASE (1000/250h) still remained in the reasonable range.

Open access
Perspectives of Autonomous Systems in Military Applications

Abstract

In the field of communication on land and in the air, there are already functioning fully or partially autonomous devices. However, it is difficult to point to similar solutions regarding autonomous systems, especially in military applications.

The article formulates development perspectives for marine autonomous systems in military applications, taking into account achieved benefits, requirements and development restrictions. Many interesting places devoted to the security of autonomous systems, on the clear improvement of the security situation with the above-mentioned systems, equipment and machines for maintenance, management devices, autonomous systems, controls and controls, devices for carrying out operations.

The recommendations indicate the need to implement joint projects in the field of the development of autonomous marine technologies and are critical in the previous activities undertaken in this field of research.

Open access
Phenomenon of Icing and a Review of Ice Accretion Nomograms, Models and Charts in Navigation

Abstract

The paper presents results of research based on analysis of marine icing nomograms, models and charts using in the sea navigation. The problem of ships icing occurs in specific weather and geographical conditions. Every year numbers of vessels navigate in these areas meet a phenomenon of icing. Ice on decks of ships can be formed from fresh water or sea (salt) water. Ships operating in waters where the phenomime of icing is occurred use for safety navigation icing nomograms and icing charts. Icing charts are created based on icing models.

The main aim of the article is to perform a review of currently used in the sea navigation icing nomograms and icing maps, based on icing models, used in navigation to depict the phenomenon of icing.

Open access
Predict of Asphalt Rutting Potential Based on IDT and Validation with ANN

Abstract

Rutting occurs due to accumulation of incrementally small permanent deformations from each load application and it can cause irreparable problems in pavements. On the other hand, the Marshall Mix design which is known as the main method in Iran, the lack of a simple test to determine specimen resistance to permanent deformation as the major reason for asphalt rutting is noticeable. Although today many devices are used for rutting measurement, none of them have the ability to use in wider field. In addition, prevalent methods of evaluating rutting potential are usually costly and time consuming. Mentioned parameters illustrate the necessity of developing a simple method, not only having fine precision, but also are able to predict rutting performance with low cost in the short term in laboratory. In this research, after performing the main tests on specimens, IDT test results and Marshall Parameters were used to develop a mathematical model to estimate specimen rut depth. The model is validated by using ANN and makes it possible to evaluate mixtures rutting potential while OBC is being determined in laboratory. So not only is there no need to use expensive instruments of rutting test, but also a remarkable time saving in mix design procedure is achievable.

Open access
Recycling of Foundry Sand Wastes in Self-Compacting Mortars: Use as Cementitious Materials and Fine Aggregates

Abstract

This work aims to study the possibility recycling of foundry sand wastes (FSW) as a cementations additive and fine aggregate in self-compacting mortars (SCM). For this, an experimental study was carried out to evaluate physical and mechanical properties of SCM. Firstly, sand is substituted by the foundry sand waste at dosages (0%, 10%, 30%, and 50%) by weight of the sand. Secondly cement is partially substituted by crushed foundry sand waste at different ratio (0%, 10%, 20%, 30%, and 50%) by weight of cement. The obtained results show that up to 50%, (FSW) can be used as fine aggregate for mortars without affecting the essential proprieties of mortar. However, beyond 50% of sand substitution, mortars lose their fluidity. The compressive strength of the mortars with 50% of cement substitution decreased compared to the control mortar. Value of the highest compressive strength recorded at 28 days, is of the order of 50 MPa for the mortar with 20% of cement substitution. Also, stress-strain curve show an acceptable mechanical behavior of FSW-based mortar at 50% of sand substitution.

Open access
Review of Normative Documents Applicable in Polish Navy in the Field of Measurement and Minimalization of Ships Physical Fields

Abstract

The article presents the general organization and operating principles of the national departmental standardization system. The characteristics of the tasks carried out in the area of defense and security, in the new formal, legal, and organizational conditions related to the passive defense of the Polish Navy ships are presented. In addition, the article contains a brief description of standardization documents in the area of national defense applied in the Armed Forces of Poland. One of the areas related to the passive defense and measurements of physical fields in the Polish Navy was also indicated.

Normalization is a way by which the Polish Navy can support the development of the military potential through the introduction of new equipment and weapons, which also contributes to the development of scientific research.

Open access
Spatial-Temporal Analysis of Land Cover and Use Changes Using Gis Tools. Case Study Băneasa Neighborhood, Bucharest

Abstract

The paper topic is related to the use of Geographic Information System and remote sensing in analysing the spatio-temporal dynamics of a post-socialist city. The purpose of this study is to highlight the changes in the land use of the Băneasa neighbourhood, located in the northern part of the capital city of Romania. The changes have been analysed from the nineteenth century to the present. The authors used historical mapping using old maps, as well as digitizing aerial photographs using the Geographic Information System. There has been an accelerated territorial evolution in the last 70 years, marked by the impact of the socialist policy of intensive urbanization, when the urban-type systematization was applied through the construction of collective dwellings, to which were added some important industrial units. After 1990, the dynamics of the tertiary sector generated significant changes in the physiognomy of the urban landscape, observing the increase of the built space (commercial spaces, new residential areas) at the expense of green spaces, tree nurseries, greenhouses and industrial sites. The most recent stage of evolution, however, has brought the most profound changes in the landscape of the Băneasa district, as a result of the new political and socio-economic context, marked by the collapse of communism. Thus, in the last 30 years, the capital city has registered an uncontrolled urban growth dynamic, this being characteristic of other large urban centres at the national level as well favoured by less strict, inconsistent and incomplete urban legislation.

Open access
Transport of Solid Particles with Fluid Flow in Rotating Pipes

Abstract

The article addresses the recent problem of borehole lifting of oil containing sand solids. The presence of sand in oil produced results in a reduced operating life of downhole equipment. The problem of preventing sanding up and sand formation in pumping equipment may be solved and stable sand production may be ensured by producing oil using borehole screw pumps with a surface-type drive, in which the screw is rotated by rotating hollow rods. Rotating hollow rods improve carry-over of sand particles to the surface with rotational oil flow by imparting additional momentum to these particles. Rotational variables of the pipe (cylinder) that enables transport of solids are set only for the air flow moving in a horizontal pipe (cylinder). The purpose of the study is to establish pipe rotational variables in directional wells that enable stable sand transport with fluid flow. Work results have been obtained from numerical studies using the differential equation system and rules of theoretical solid movement, computer simulation and experimental results processing at a laboratory facility. Theoretical study results have been acknowledged by experimental studies. The work establishes the criteria that allow defining the speed range of directional hollow rods that enables carry-over of solids to the surface with fluid flow. Study results may be used to produce oil with submersible screw pumps with a surface-type drive that use hollow sucker rods for pump down.

Open access
Applying of Neural Networks for Testing of Tracers with using of Empirical Data

Abstract

An attempt of designing artificial neural networks for empirical laboratory test results tracers No. 5, No. 7 and No. 8 was introduced in the article. These tracers are applied in cartridges with calibres from 37 mm to 122 mm which are still used and stored both in the marine climate and land. The results of laboratory tests of tracers in the field of over 40 years of tests have been analysed. They have been properly prepared in accordance with the requirements that are necessary to design of neural networks. Only the evaluation module of these tracers was evaluated, because this element of tests, fulfilled the necessary assumptions needed to build artificial neural networks. Several hundred artificial neural networks have been built for each type of analysed tracers. After an in-depth analysis of received results, it was chosen one the best neural network, the main parameters of which were described and discussed in the article. Received results of working built of neural networks were compared with previously functioning manual evaluation module of these tracers. On the basis conducted analyses, proposed the modification of functioning test methodology by replacing the previous manual evaluation modules through elaborated automatic models of artificial neural networks. Artificial neural networks have a very important feature, namely they are used in the prediction of specific output data. This feature successfully used in diagnostic tests of other elements of ammunition.

Open access
Emulator and Simulator of Term a SCANTER and ARPA Radar Data Server

Abstract

The software solutions presented in this paper generate real-time data compatible with ARPA radar standard as well as Terma SCANTER 2001 radar cooperating with Video Distribution and Tracking (VDT) server. Two different approaches to this problem are considered: emulation based on the data captured from real devices and simulation of objects on the sea. For both of them architecture, implementation details and functional test results are presented. The developed software will be used to test new functionalities of the multimedia surveillance system implemented for the Maritime Division of the Polish Border Guard within the STRADAR project.

Open access