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Number of results: 7
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Abstract

The aim of this study is to find the cost design of RC tension with varying conditions using the Artificial Neural Network. Design constraints were used to cover all reliable design parameters, such as limiting cross sectional dimensions and; their reinforcement ratio and even the beahviour of optimally designed sections. The design of the RC tension members were made using Indian and European standard specifications which were discussed. The designed tension members according to both codes satisfy the strength and serviceability criteria. While no literature is available on the optimal design of RC tension members, the cross-sectional dimensions of the tension membersfor different grades of concrete and steel, and area of formwork are considered as the variables in the present optimum design model. A design example is explained and the results are presented. It is concluded that the proposed optimum design model yields rational, reliable, and practical designs.
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Abstract

The contemporary underground mining of raw minerals is more and more associated with geological and mining software packages which support the work of designers from the moment of the exploration of a deposit, determination of its size and quality, geological, hydrogeological and tectonic conditions, by planning the development and cutting of the deposit. Production planning is one of the most important activities carried out in the course of a mining project, because it allows to set specific production results of a mine in relation to a time unit, and then allows for a verification of the degree of completion of the assumed plan. At present, computer-aided design is applicable to daily or long-term output planning taking deposit, qualitative, quantitative and cost constraints into account. In the article, selected forms of ore deposits were presented. On the basis of several dozen boreholes up to 300m in length, an exemplary fragment of the ore cutting model using computer-aided design of mining works was presented. By using modern computer software - ABB MineScape with modular construction, the possibilities of improving the process of development of future exploitation areas have been determined. In particular, the arrangement of boreholes, based on which ones the cross sections were made with, present the exemplary lithostratigraphic thickness of layers, including the location of discontinuous deformations in the form of faults, and an ore bearing zone. For the block model, resources with priority for metal N o. 1 and 2 were calculated. I n the last section of the article, the cutting idea for a shallow ore deposit has been presented. The degree of effective use of the deposit has been analysed for the room and pillar mining method.
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Abstract

This study aims to design a novel air cleaning facility which conforms to the current situation in China, and moreover can satisfy our demand on air purification under the condition of poor air quality, as well as discuss the development means of a prototype product. Air conditions in the operating room of a hospital were measured as the research subject of this study. First, a suitable turbulence model and boundary conditions were selected and computational fluid dynamics (CFD) software was used to simulate indoor air distribution. The analysis and comparison of the simulation results suggested that increasing the area of air supply outlets and the number of return air inlets would not only increase the area of unidirectional flow region in main flow region, but also avoid an indoor vortex and turbulivity of the operating area. Based on the summary of heat and humidity management methods, the system operation mode and relevant parameter technologies as well as the characteristics of the thermal-humidity load of the operating room were analyzed and compiled. According to the load value and parameters of indoor design obtained after our calculations, the airflow distribution of purifying the air-conditioning system in a clean operating room was designed and checked. The research results suggested that the application of a secondary return air system in the summer could reduce energy consumption and be consistent with the concept of primary humidity control. This study analyzed the feasibility and energy conservation properties of cleaning air-conditioning technology in operating rooms, proposed some solutions to the problem, and performed a feasible simulation, which provides a reference for practical engineering.
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Abstract

The economic envelopes obtained by optimization techniques in open pit mining are transformed into operational phases that are suitable for extraction through ramp designs. This process is performed with the aid of specialized design software, which is still very manual, time consuming and highly dependent on the expertise of the planner. In this paper, we introduce a new methodology based on a mathematical model to automatically propose the design of ramps from the economic envelope of a pushback, with the resulting envelope having the maximum value. The developed model was tested against a real case scenario showing reasonable and useable solutions for the planner. Using this approach, a planner can evaluate several alternatives in a reasonable time before selecting the final design.
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Abstract

In the paper, a procedure for precise and expedited design optimization of unequal power split patch couplers is proposed. Our methodology aims at identifying the coupler dimensions that correspond to the circuit operating at the requested frequency and featuring a required power split. At the same time, the design process is supposed to be computationally efficient. The proposed methodology involves two types of auxiliary models (surrogates): an inverse one, constructed from a set of reference designs optimized for particular power split values, and a forward one which represents the circuit S-parameter gradients as a function of the power split ratio. The inverse model directly yields the values of geometry parameters of the coupler for any required power split, whereas the forward model is used for a post-scaling correction of the circuit characteristics. For the sake of illustration, a 10-GHz circular sector patch coupler is considered. The power split ratio of the structure is re-designed within a wide range of ��6 dB to 0 dB. As demonstrated, precise scaling (with the power split error smaller than 0.02 dB and the operating frequency error not exceeding 0.05 GHz) can be achieved at the cost of less than three full-wave EM simulations of the coupler. Numerical results are validated experimentally.
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Abstract

City is a formal expression of social relations. It is a kind of ethos and dreams connected with history and identity of individuals. It is a structure with thousands of meanings. The opportunities it creates can lead to an outstanding civilization. At the same time it reveals all negative aspects of living. City is a collection of separate individuals combined with common perception of spatial affi liation and identity development. It is worth writing about city because despite its well-defi ned value it is an elusive being. In spite of being a kind of collective needs it is still on the move, transforms all the time reflecting human emotions. Existence of city as a phenomena itself is a symbol of realization of people’s most basic needs and the history of its development shows growing complication and diversification of expectations related to it. City along with is diversity reflects human beings of a particular time. It is a spotlight in which both successes and failures of communities and individuals in each epoch can be seen. Thanks to its interdisciplinary character it can be perceived as multidimensional place. It is a multifaceted organism with high hopes and unlimited opportunities. Differences in perception which are due to a number of its users results in a wide range of problems and expectations. Expectations of local communities and individuals of a whole city vary. As a result, what we call a city landscape must be very vague and differs depending on a particular field which is taken into consideration. The number of opportunities and city-related issues is infi nite. In the dissertation below, however, three factors are the crucial ones: structure, meaning and city phenomena as a landscape. Thanks to the interpretation of model and genius loci as well as defining social expectations we have managed to conceive the phenomena of spatial identity. We have decided on this method referring directly to the concept of landscape. City is in here widely defined between urban aspects of landscape and city landscape. We have tried to understand what city is in terms of landscape, where it comes from and where it goes to. It is a trial of translation the Gaugin’s method: where are we from? Who are we? Where are we going to? into the language of present perception of some particular aspects of town planning. We live at times of the unprecedented technological change which is followed by a social change. It all must have an impact on how city is perceived, what it looks like, how it is to live there and what it is going to be like – what the future has in store. We have tried to bring the reader’s attention to the problems and issues which had appeared before the advent of reality we live in. We have focused on what may have led to a kind of city crisis at the edge of 19th and 20th centuries and some radical solutions trying to overcome the arisen problems and its consequences today. Both its pompous character and sentimentalism of town planning and architecture in the early 20th century have made us be bored with form which is felt in many parts of the world even today. Another aspect of our work covers understanding city in social terms as well as contemporary and future solutions. We are of the opinion it is worth asking questions referring to the future and at the same time regarding its current state and recent past. It is commendable to look for particular tools and solutions. Three dimensions which are covered by the book are figurative. Structure – which is everything we perceive as a kind of a template, identifi cation – we assign to city. It is responsible for recognition, adaptation to some forms by which we defi ne space. Meaning is a step forward. While the structure’s equivalent is „I can see”, the meaning equals to „I know”. Meaning does not exist as a city without structure just like structure does not exist without meaning. Things don’t just exist, they have some characteristics and purpose and it refers to trees, buildings and all other urban elements constituting city in all steady and temporary aspects and time dimensions. Meaning is also interpretation and emotion regarding both community and individual. It is the answer to the question „why?” Some particular places and spaces are linked to some particular values which identify them. This system of values is a must to be able to interpret what space we are dealing with and its diagnosis. Meaning is very much about social aspect too. It has to do with perception and remembering city and it is connected with knowledge, tradition and culture of places. Another aspect linked to relations in city landscape combines other aspects and constitutes something to which city refers to. Phenomena is contribution and verifi cation. The way city works is fundamental to all city residents and users. A key to such understanding a city is the term of genius loci. By singling out objects, order, time, character and light we are able to widely identify essence of space and particular places. The graphic model by Panofsky acts here as a verifying tool. City landscape as a form is of great importance here. The sense of beauty is as essential as the way the city works. Social perception of city is not only shaped by the way it is used, but also by the fact what city is like and how it is perceived. Spatial order is an incredibly important factor understood here as everything what accommodates vaguely defi ned beauty and what is connected with its particular structure, history and identity. All these factors contribute to the value of city landscape. When it comes to city landscape studies social aspect is emphasized by the impact of humanities, especially sociology, which perfectly shows expectations related to space. Cities are built and seen in the context of particular tradition, culture and history. Their skyline and ways of functioning are embedded in mentalities of societies which they represent. Despite their diversity from the global point of view they are susceptible to similar trends resulting in crisis or prosperity periods. They are economic archetypes of success.
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Abstract

At the early stage of information system analysis and design one of the challenge is to estimate total work effort needed, when only small number of analysis artifacts is available. As a solution we propose new method called SAMEE – Simple Adaptive Method for Effort Estimation. It is based on the idea of polynomial regression and uses selected UML artifacts like use cases, actors, domain classes and references between them. In this paper we describe implementation of this method in Enterprise Architect CASE tool and show simple example how to use it in real information system analysis.
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