Knowledge Extraction and Visualization from Textual Sources Intended for Construction Project Management

Током животног циклуса инвестиционог пројекта ствара се велики корпус неструктуираних и полуструктуираних докумената. Традиционални приступи у складиштењу и организовању информација из неструктуираних податка су оријентисани на рад са документима, што их чини неподесним за анализу и издвајање знања. У неструктуираним документима је отежано прикупљање, анализа и поновно коришћење релевантних информација у интегралном облику, што може изазвати проблеме на пројекту услед неблаговремених или неодговарајућих одлука. У овој дисертацији је приказана репрезентација информација издвојених из неструктуираних текстуалних докумената у облику графа значајних фраза, који корисницима треба да омогући визуелизацију и анализу значајних чињеница на пројекту са минималном количином уложеног труда. Са циљем да се конструише доменски независна репрезентација са минималним трудом експерта за претходно конфигурисање, значајне фразе су детектоване у вишејезичном окружењу применом статистичких мера за одређивање корелисаности пара речи. Граф садржи аутоматски издвојене значајне фразе које су повезане на основу сличности семантичких контекста. Репрезентација је имплементирана у графовској бази података што корисницима омогућава да детектују и визуелизују различите скривене обрасце у подацима. Неинформативне фразе су филтриране кроз поступке одређивања ентропије скупа контекста и динамичности суседства фразе кроз више графова који представљају тренутке у времену. Приказана је хеуристика за издвајање комплексних концепата, заснована на итеративној процедури за детекцију блиских фраза које припадају истом семантичком подграфу. Могућности примене предложене репрезентације су демонстриране на графу конструисаном за постојећи корпус докумената са међународног инвестиционог пројекта.During a construction project lifecycle, an extensive corpus of unstructured or semi-structured text documents is generated. Traditional approaches for information storing and organizing are document-oriented, which is highly inconvenient for data analysis and knowledge extraction. The nature of unstructured sources impedes users’ acquisition, analysis, and reuse of relevant information, leading to possible negative effects in the project management process. This dissertation suggests a procedure for automatic extraction of relevant project concepts from unstructured text documents. Concepts are organized in the form of a key-phrase network, intended to provide users with the possibility to visualize and analyze valuable project facts with less effort. With the objective of constructing a domain-independent and language-independent key-phrase network, with minimal expert involvement for configuration, an approach to detect key phrases was examined by using measures of correlation for word pairs. A network contains key phrases automatically extracted from various types of unstructured documents, with relations based on the similarity of semantic contexts. The representation was implemented as a graph database, enabling project participants to extract and visualize various patterns in data. The problem of noisy key phrases was reduced by introducing the entropy score for a set of co-occurring contexts and the measure of phrase neighborhood dynamics throughout construction project lifecycle. A heuristic for extraction of complex concepts is presented, based on the iterative procedure for detection of adjacent key phrases belonging to a same semantic subnetwork. Possible applications, such as concept tracking through time or determination of communication patterns between project participants, is demonstrated using a key-phrase network generated for the existing document corpus from an international construction project

Computational design and analysis of tensegrity structures

The paper presents the application of computational tools in design and analysis of integrally tensioned (tenegrity) structures. The shaping process of this specific type of spatial structures is determined by consideration of form-structure interrelation. Therefore, the sustainable approach to their design implies the application of tools which could both represent geometry and simulate their physical behaviour. With respect to this, in the research we tested the application of computational tools Fasttens for design of tensegrity structures. Fasttens programme is based on the computational procedure for non-linear analysis of tensegrity systems originally developed by Miodrag Nestorović. In order to run the original programme written in Turbo Pascal, we performed emulation, using emulator software DOSBox. We tested the application of the tool in the design of concrete tensegrity structure. Presented design and numerical experiment confirmed the effectiveness of the proposed approach

Novel methods for axial fan impeller geometry analysis and experimental investigations of the generated swirl turbulent flow

Geometry analysis of the axial fan impeller, experimentally obtained operating characteristics and experimental investigations of the turbulent swirl flow generated behind the impeller are presented in this paper. Formerly designed and manufactured, axial fan impeller blade geometry (originally designed by Prof Dr-Ing. Z. Protic(dagger)) has been digitized using a three-dimensional scanner. In parallel, the same impeller has been modeled by beta version software for modeling axial turbomachines, based on modified classical calculation. These results were compared. Afterwards, the axial fan operating characteristics were measured on the standardized test rig in the Laboratory for Hydraulic Machinery and Energy Systems, Faculty of Mechanical Engineering, University of Belgrade. Optimum blade impeller position was determined on the basis of these results. Afterwards, impeller with angle 22 without outlet vanes, was positioned in a circular pipe. Rotational speed has been varied in the range from 500 till 2500 rpm. Reynolds numbers generated in this way, calculated for axial velocity component, was in the range from 0.68.10(5) till 2.5.10(5). Laser Doppler anemometry measurements and stereo particle image velocimetry measurements of the three-dimensional velocity field in the swirl turbulent fluid flow behind the axial fan have been performed for each regime. Obtained results point out extraordinary complexity of the structure of generated three-dimensional turbulent velocity fields

Faktori koji doprinose kašnjenju projekta iz perspektive izvođača radova: studija slučaja - građevinski projekti putne infrastrukture u Srbiji

Infrastrukturni projekti su kapitalni projekti koji su veoma složeni u pogledu obima, trajanja i velikog broja učesnika. Prema postojećim studijama, prekoračenje vremena građevinskih projekata je jedan od najčešćih problema. Cilj ovog istraživanja je da se identifikuju uzroci kašnjenja u cilju razvoja mera za ublažavanje ili otklanjanje potencijalnih rizika i uspešnog završetka projekta u planiranom roku. Da bi se postigao definisani cilj, sprovedeno je empirijsko istraživanje kako bi se identifikovali glavni uzroci kašnjenja na projektima putne infrastrukture iz perspektive izvođača radova. Anketa je obuhvatila 53 uzroka kašnjenja grupisanih u 8 kategorija. Ukupno 35 izvođača je učestvovalo u empirijskom istraživanju. Rezultati su pokazali da su najčešći uzroci koji prouzrokuju prekoračenje vremena problemi sa projektnom dokumentacijom i tenderske procedure. Doprinosi ovog istraživanja mogu biti od koristi u cilju poboljšanja vremenskih performansi na projektima putne infrastruktur

Keyphrases analysis of BIM standards through occurrence of most common BIM uses

The 8th PSU-UNS International Conference on Engineering and Technology (ICET-2017), Novi Sad, Serbia, June 8-10, 2017 University of Novi Sad, Faculty of Technical Sciences Abstract: Building Information Modeling (BIM) does not represent only the virtual model of the facility but a comperhensive approach consisting of technology, processes, stakeholders' behavior and accompanying standards.Given the fast evolution of BIM, this paper is analysing trends of development of BIM standards throughout the years by applying the keyphrases analysis method, for some of the most common BIM uses and recognizable phrases in BIM industry

Application of unstructured text based features in prediction of real estate prices: A comparative study

This study demonstrates the potential of application of unstructured textual data for predicting real estate prices and compares different protocols for extracting features from textual data. Performance of the different models for price prediction was evaluated on data set of real estate listings, which included numerical and categorical features, as well as text descriptions. The experiments showed that adding features extracted from both the translated description text, as well as noun chunks from it, resulted in the highest R2 score of 0.768, representing an improvement over the R2 score of 0.71 for the baseline model without text-based features. The findings from this study indicate how the performance of real estate price prediction models can be improved by utilizing text-based features, in turn benefiting property market stakeholders in making informed decisions and evaluating competitive pricing strategies

Fluid boundaries shaping using the method of kinetic balance

Fluid flow in curved channels with various cross-sections, as a common problem in theoretical and applied fluid mechanics, is a very complex and quite undiscovered phenomenon. Defining the optimum shape of the fluid flow boundaries, which would ensure minimum undesirable phenomena, like "dead water" zones, unsteady fluid flow, etc., is one of the crucial hydraulic engineering’s task. Method of kinetic balance is described and used for this purpose, what is illustrated with few examples

Defining the optimum shape of the cross-flow turbine semi-spiral case by the Lagrange’s principle of virtual work

Određivanje optimalnog oblika strujnog prostora sa minimumom negativnih pojava (mrtva voda, nestacionarne pojave i dr) je vrlo važan zadatak inženjera hidrotehnike. U ovom radu se prikazuje metoda koja je zasnovana na Lagranžeovom principu virtuelnog rada. Metoda je primenjena pri oblikovanju uvodne komore Banki turbine.Determination of the optimal flow field boundary with minimum undesirable phenomena (dead water zones, unsteady fluid flow, etc) is a very important task in hydraulic engineering. This paper presents one method based on the Lagrange’s principle of virtual work. The method was used for defining intake case of cross-flow(Bunki) turbine

Defining the optimum shape of the cross-flow turbine semi-spiral case by the Lagrange’s principle of virtual work

Određivanje optimalnog oblika strujnog prostora sa minimumom negativnih pojava (mrtva voda, nestacionarne pojave i dr) je vrlo važan zadatak inženjera hidrotehnike. U ovom radu se prikazuje metoda koja je zasnovana na Lagranžeovom principu virtuelnog rada. Metoda je primenjena pri oblikovanju uvodne komore Banki turbine.Determination of the optimal flow field boundary with minimum undesirable phenomena (dead water zones, unsteady fluid flow, etc) is a very important task in hydraulic engineering. This paper presents one method based on the Lagrange’s principle of virtual work. The method was used for defining intake case of cross-flow(Bunki) turbine

Fluid boundaries shaping using the method of kinetic balance

Fluid flow in curved channels with various cross-sections, as a common problem in theoretical and applied fluid mechanics, is a very complex and quite undiscovered phenomenon. Defining the optimum shape of the fluid flow boundaries, which would ensure minimum undesirable phenomena, like "dead water" zones, unsteady fluid flow, etc., is one of the crucial hydraulic engineering’s task. Method of kinetic balance is described and used for this purpose, what is illustrated with few examples