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Öğe 01-039-Anomalies of the RRH and RID resource distribution metrics(Asociacion Espanola de Direccion e Ingenieria de Proyectos (AEIPRO), 2025) Bettemir, Onder HalisResource leveling aims to reduce the fluctuations of the resource distribution and peak resource demand during the construction. Obtaining the optimum solution is not a problem as the optimization tools can be accessed easily and large problems can be solved by ordinary desktop computers. However, the most important part of the problem is the selection of the proper metric, because all of the resource distribution metrics do not reduce the fluctuations or peak resource demand. In this study, drawbacks of resource idle day, release and rehire, and minimum moment metrics are discussed on case study problems in which the examined metrics cannot provide proper resource distributions. Resource idle day, and release and rehire metrics cannot penalize peak resource demand properly while they may excessively penalize unimportant fluctuations. Minimum moment metric cannot penalize resource fluctuations efficiently and systematically. Project managers may face with even worse resource distribution if the aforementioned metrics are utilized without any prior knowledge. © 2025 by the authors.Öğe 02-030 – Adverse consequences of unbalanced governmental aids after the February 6 2023 earthquakes(Asociacion Espanola de Direccion e Ingenieria de Proyectos (AEIPRO), 2025) Bettemir, Onder HalisThis study examines and criticizes unbalanced governmental aids that are announced after the February 6 2023 earthquakes. The governmental aids were not related with the value of the damaged property and same aids are provided to the victims which may cause charity hazard for the owners of low value real estates. On the other hand, owners of the high value real estates tried all legal means to have their buildings repaired which may led to retrofit of unsuitable buildings. The state offers grants and low-interest support for the reconstruction of demolished buildings by property owners on the same site. The problems of these situations are that most of the demolished buildings are demolished because they were built on unsuitable ground, and people with no construction experience will be managing contracts with experienced contractors. During the constructions, the contractors will probably ask for price increase and construct the buildings with low quality material and poor workmanship as they do not have to sell them since the customers have to accept the constructed facility. © 2025 by the authors.Öğe Analysis of Embodied Energy and Carbon Emission of a Single Story Rural Area Structure(Gazi Univ, 2023) Erzurum, Tugba; Bettemir, Onder HalisDetermining and analyzing the adverse consequences of construction works on the environment is an important research area. The necessity of execution of a large number of work items for the construction of a building and the large number of building material options make it difficult to conduct embodied energy and carbon emission analyzes of building constructions. In this study, a framework system is developed to overcome the mentioned difficulties. Construction items of a typical single -story building that can be built in the rural region are arranged and different construction options are generated for the construction items. The amounts of material and construction equipment requirements for the unit construction item of all construction options are computed. Semantic relationships between the building elements and the construction alternatives are established so that the quantity values that may vary according to the selected work item can be calculated exactly. Cost, embodied energy and carbon emissions caused by the construction of the building are calculated by matching the quantity values with the unit construction item definitions. Moreover, the heat loss calculations of the building are carried out according to TS 825 and the energy consumption, carbon emission and cost that will occur as a result of the utilization of wood, coal, electric stove and air conditioner options as heating source during its 50 years of life cycle are calculated. In order to examine the effects of construction items on the embodied energy, carbon emission and cost, Monte Carlo simulation is implemented by forming the building with random selections for each construction item among the defined construction options with equal probability of selection. At the end of the simulation the total embodied energy, carbon emission and cost of both the construction and the utilization phases of the structure are calculated. In this manner, the average embodied energy, carbon emission and cost effect of each of the construction items on the structure are determined. Prepared embodied energy and carbon emission quantities of the construction items and the analysis results presented within this study have the potential to be beneficial to the researchers studying on green buildings.Öğe Analysis of Existing Resource Distribution Metrics and Suggestion of New Metrics(Asce-Amer Soc Civil Engineers, 2025) Bettemir, Onder HalisResource leveling aims to reduce peak resource demand and fluctuations in resource usage histograms throughout a construction period. The objective function optimum can be obtained in the digitalized construction management era. However, the correct quantification of uneven resource distribution is also essential because an improper resource distribution metric may even worsen the resource distribution. The behaviors of existing resource distribution metrics were not examined thoroughly in the literature. This study aims to improve existing resource distribution metrics and analyze the objective functions to identify their positive and negative aspects. Eight existing resource leveling metrics were analyzed by considering their responses to the peak resource demand and fluctuations in daily resource demand. The analysis uncovered that the existing metrics were insensitive to either resource fluctuations or peak resource demand. The time insensitiveness of the minimum moment metric was eliminated by merging it with the sum of the square metric. In addition, a fractional order resource distribution metric was proposed to dissuasively penalize peak resource demand. A comparison of resource distribution metrics for two case study problems revealed that the proposed three resource distribution metrics presented better resource distribution histograms with less fluctuations and peak resource demand. This study revealed the behavior and disadvantages of existing resource distribution metrics such that the schedulers can foresee the probable output of the metrics, which may assist them in implementing a proper metric. Moreover, the metrics developed in this study provided better resource histograms, which was the theoretical contribution of this study.Öğe Assessment of Blind-Spots and Multi-Path Effects at Indoor Positioning by Multilateration(Copernicus Gesellschaft Mbh, 2025) Dogan, Nezir; Bettemir, Onder HalisIndoor positioning techniques are utilized in many professional applications. However, aforementioned technique can provide positions with serious accuracy problems due to multipath and ill-conditioned station constellations. In the literature the effect of multipath is examined thoroughly but the ill-conditioned station constellations are omitted. In this study, indoor positioning accuracy is examined by simulation where white Gaussian noise is added to the exact distances between the location to be measured and the station points. Effect of station constellation is analyzed by trying two different station positions. In the first case all of the stations are located at the same side of the room causing nearly parallel lines among the location and station points. In the second case all of the stations are located at different sides of the room and ill-conditioned systems are avoided. The simulation results provided that when the location to be measured and the stations are located at the same line, the measurement errors are magnified by the illconditioned least square-adjustment equations which leads to significant positioning errors. Moreover, an algorithm for the detection of multipath is proposed and tested by simulation. The algorithm detected 31 multipath cases among the 35 multipath situations and significantly improved the resultant positioning accuracy. The simulation results illustrated that the proposed multipath detection algorithm can be utilized efficiently for indoor positioning applications.Öğe Autonomous Grading Maneuver Determination Algorithm for Electric Dozers(Wiley, 2026) Bettemir, Onder HalisState-of-the-art autonomous grading algorithms can handle small regions and simple tasks due to their high computational loads. To address the aforementioned literature gap, this study presents an algorithm that heuristically calculates the excavation, transportation, dumping, and return maneuvers required for autonomous excavation. The algorithm is particularly developed for electric dozers with limited power. The algorithm starts from the opposite side of the dump zone and begins excavation from the local maximum height to avoid upward excavation and hauling to minimize the resistive forces acting on the dozer. The excavation depth and hauling capacity were defined so as not to exceed the electric dozer's power. Excavation of an area of 45 m wide and 60 m long was simulated by considering the effects of the open circuit voltage drop of the batteries. Simulations were completed between 16 and 64 s, depending on the configuration of the electric dozer. Regression analysis revealed that computation time increases linearly with an increase in width and quadratically with an increase in length. Simulations demonstrated that the proposed algorithm is suitable for electric dozers with low rimpull.Öğe BIM-driven software and algorithm for optimal floor tile layout minimizing material waste(Elsevier, 2025) Ergen, Faruk; Bettemir, Onder HalisState-of-the-art BIM software cannot provide effective solutions for tile placement across spaces due to inaccurate quantity take-off (QTO), internal obstacle recognition, and 3D visualization. This prevents minimizing the waste material of floor covering. In this paper, BIM-based software is developed to establish semantic relationships between the covered surface and the room's structural and architectural elements to compute exact QTO. A tile layout algorithm is embedded to the software which considers the geometry of the room, the obstacles inside the room, and tile size to determine the most efficient layout that minimizes material cut and waste. The algorithm reduced material waste up to 73 % in case studies conducted to validate the proposed approach. The BIM-based software is beneficial for designers and construction firms, reducing material waste and promoting sustainability. The solution inspires future work on more efficient algorithms for tile layout design and BIM-based waste assessment of construction activities.Öğe Comparative life cycle assessment of post-disaster housing according to ground type-outdoor temperature-lifespan relationship: Carbon, energy and cost(Elsevier, 2025) Bettemir, Onder Halis; Erzurum, TugbaSite selection of accommodation facilities after the destructive earthquakes usually ignores the trade-off between the bearing capacity of the soil and the micro climate effects. In this study, effects of bearing capacity of the soil on the foundation and micro climate on the heating requirement of the facility are considered based on the cost, carbon, and energy throughout the construction as well as two, five and fifty years of utilization period. The effects of ground type, outdoor temperature, insulation thickness, and use period of the buildings are determined by considering carbon, energy and cost criteria. Environmental effect of the construction is analyzed by detailed definitions of the construction items which provide necessary data to compute the material requirements and energy consumption. Required energy for the heating of the buildings is computed according to the Turkish Standard 825. Scenario analyzes considering different site locations and insulation thicknesses are implemented to determine the most appropriate disaster recovery housing location to minimize the overall environmental impact. The proposed approach aims to minimize effects by analyzing the cost and environmental effects of the both temporary and permanent buildings. It also determines the most appropriate location of structures to be constructed after the disaster to minimize the overall environmental impact and cost, which provides cleaner disaster management opportunity for the authorities.Öğe Cost and duration estimation of autonomous grading algorithm by simulation(Yildiz Technical Univ, 2024) Bettemir, Onder HalisEstimation of cost and duration of grading a particular area provides important information for contractors and construction machine manufacturers. In this study, cost and duration of excavation by dozer is estimated by simulating the movements of the dozer. Specifications of the dozer, soil conditions and site conditions are defined to the simulator. The simulation considers tire penetration, rolling, grade, hauling, as well as cutting resistances and estimates the necessary force to be applied. The simulation implements an autonomous grading algorithm established for electric powered dozers which starts grading from a local highest point to prevent uphill excavation and hauling. The algorithm determines the necessary maneuvers to reach local highest point, excavate or haul the earth pile to the dump area. The simulation runs until the objected elevation is obtained at each portion of the excavation site. The simulator calculates the consumed energy, time, and total cost of the excavation. The excavations of 30x45 square meter area by one existing electric dozer and five updated versions of it are simulated. The simulation of the excavation is computed in 23 seconds for the smallest and 10 seconds for the largest dozer. The cost of grading and pushing the excavated material at most 20 meters away is estimated as less than 5 cents/m3 for the lead-acid battery powered dozer and 8 cents/m3 in the average for the lithium-ion battery powered dozers. The simulation revealed that electric powered dozers have less unit excavation cost than diesel powered ones, also larger dozers consumes less energy than the smaller ones. The developed simulation technique is implemented without any numerical errors and the technique can be beneficial for the construction machine manufacturers to optimize their designs and for the contractors to select the most suitable construction machine among the present alternatives.Öğe Detection of Railway Track from Image by Heuristic Method(Ieee, 2015) Bettemir, Onder HalisDefects on the railway track occur due to the abrasive effects of time and usage. As the magnitude of the defects increases, uncomfortable travel appears. If the defects progress further they may cause derailment of the train. Detection of the defects are performed by manual inspection of the track, which cause ignorance of some of the defects. In this study a heuristic algorithm, which detects railway track from the images acquired by unmanned vehicle, is developed. Rails and sleepers of the railway track is detected with high accuracy from the images acquired in nadir direction. Images are de-noised by Gauss filter and edges are detected by Prewitt Edge Detection algorithm. By considering the geometric properties of the railway track and the brightness values of the edges, the Heuristic algorithm decides on which edges belong to railway track. In this study, inspection of railways is proposed by the images acquired by unmanned aerial vehicles and the automated detection of railway elements are realized as the first step of the railway inspection.Öğe Determination of Search Domain of Resource Constrained Project Scheduling Problem(Asociacion Espanola de Direccion e Ingenieria de Proyectos (AEIPRO), 2024) Bettemir, Onder HalisResource constrained project scheduling is an important problem of construction management. Procurement of excessive number of resources significantly increases the total project cost. Therefore, restrictions on the number of resources are defined and the optimum solution of resource constrained project scheduling problem provides the shortest project completion time. The aforementioned problem is NP-Hard since the search domain of the problem increases exponentially if the number of activities increases. In this study, the size of the search domain of the problem is examined by considering the number of activities. Contributions of the activities on the serial and parallel paths are examined. Equations representing the size of the search domain against the number of activities are derived for the aforementioned situations. The provided relationships represent the difficulty of the examined problem. Researchers can implement more robust optimization algorithms by considering the difficulty of the problem. © 2024 by the authors.Öğe Determination of Thermal Bridge of the Buildings from Infrared Images(Gazi Univ, 2023) Bettemir, Onder HalisVast majority of the existing buildings in Turkiye are not inspected for thermal insulation quality during the construction process therefore, thermal insulation performance of the existing buildings cannot be known. Measuring the thermal insulation performance of the buildings by scraping the plaster and examining the heat insulation material is not a viable solution when the size of the building stock of Turkiye is considered. In this study, detection of thermal bridges of the buildings by processing the thermal images of the buildings is proposed. The method is based on the binarization of the thermal image by the classification of the building elements as heat loss element or no heat loss element by analyzing the thermal image of the building. Global threshold methods and adaptive local threshold methods applied for binarization. All of the implemented methods require a threshold value for the classification. Determining a valid threshold value for all images is not possible therefore the threshold value is determined by the Otsu algorithm. Threshold determination process is executed both on the thermal image and the edge image. Obtained threshold values are implemented on the thermal images and the edge images. Local edge detection algorithms derived from the literature are compared by examining five thermal images and the comparison revealed that the Modified II Frei-Chen and Second-order Laplace operator provided the most suitable result. The case studies revealed that the thermal insulation performance of the existing building stock can be determined quickly, economically and reliably by implementing the proposed method.Öğe Development of a Formwork Deflection Measurement System for Construction Site Safety and Quality Assurance(Copernicus Gesellschaft Mbh, 2025) Dogan, Nezir; Uzunkaya, Ali; Bettemir, Onder HalisIn this study a low-cost real-time monitoring system to detect deflection of scaffolding for the formwork is designed and it is implemented on construction sites. The developed system uses HC-SR04 ultrasonic distance sensors to measure the distance between the ground and the ceiling formwork. Successive distance measurements relieve the deflection of scaffold components and the data is transmited to a central computer via 433 MHz RF modules. The distance measurements are based on the speed of sound and in order to enhance the accuracy of the measurements a DHT11 temperature sensor is incorporated into the system to account for temperature induced changes in speed of sound. The use of low-cost, easily replaceable sensors ensures usability of the developed system on construction sites where against environmental conditions such as physical impacts and heavy dust are commonly encountered. The ultrasonic sensors are activated sequentially to reduce interference and more accurate distance measurements are obtained. The system is designed to ensure easy installation which makes it adaptable to various construction environments. The distance data collected by the sensors are processed through a central computer. Recent measurements with baseline data gathered at the beginning of the concrete placement process are compared. This assists detecting significant changes on the scaffolding system such as excessive settlement or deformation, which could jeopardize the safety of the formwork structure. The proposed system offers an efficient, cost-effective, and scalable solution for real-time monitoring of the deflection of the scaffolding for the formwork. Consequently it ensures structural stability, construction safety, and quality of concreting tasks.Öğe Development of ontological algorithms for exact QTO of reinforced concrete construction items(Elsevier Science Inc, 2024) Ergen, Faruk; Bettemir, Onder HalisBuilding Information Modeling (BIM) provides significant benefits to the construction industry throughout the project management process. However, state-of-the-art BIM software provides erroneous quantity take -off (QTO) results above the negligible margin. In this study, QTO calculation algorithms have been developed for rough construction and implemented on BIM software to solve the stated problem. The developed QTO algorithms establish semantic relations and search the neighborhood of the structural elements to detect the intersecting structural elements. Amount of intersection is calculated by the dimensions and the locations of the intersecting structural elements. Exact length and spacing of the rebar and stirrups are calculated by considering the created semantic relationships. QTO of formwork is accurately calculated by considering the voids of the QTO computations which are obtained from the constructed semantic relationships by investigating the column -beam, slabbeam, and slab -column contact areas. Furthermore, the construction type of the scaffolding for the formwork is determined by considering both the dimensions of the structure and the established semantic relations. The developed algorithms are executed on BIM capable software and tested in four case studies with special conditions. The comparison with manual condition revealed that the proposed algorithms provided exact results. The semantic QTO algorithms developed in this study have the potential to be useful for BIM software developers.Öğe ERROR ANALYSIS OF VISUAL ODOMETRY FOR A SMALL SIZE UNMANNED AERIAL VEHICLE(Copernicus Gesellschaft Mbh, 2024) Bettemir, Onder HalisUsage of small size Unmanned Aerial Vehicle (UAV) with autonomous flight capability became widespread at both civil and military applications because of its low costs and ease of use. However, inertial or GPS based positioning and orientation sensors can be disabled at battlefields and the UAV losses its path in a short time. Visual odometry becomes a solution for the aforementioned hassle. Real-time detection of ground control points, matching the same control points at the stereo pair images and correcting the position and orientation data with least square adjustment are the challenges of visual odometry. In this study, error analysis of position and orientation of a UAV flying through mountainous region which cannot obtain any augmenting data for position and orientation is conducted by error propagation law. The flight of UAV is simulated with exact initial position and orientation data. Optic images of ground obtained by nadir directed camera are georeferenced using the digital elevation model of the region, interior and exterior camera parameters. The digital elevation model is used to correct the relief displacement. The stereo-pair image is obtained when the UAV flies 200 m and image coordinates of the common control points are detected by colinearity equations. Position and orientation of UAV is corrected by least square adjustment and the process is repeated for each obtained image acquired at 200 m interval. The analysis revealed that the precisions of horizontal and vertical positioning becomes 75 and 200 meter, respectively. The precision of roll angle becomes worse than 0.5 degree, while the precisions of pitch and yaw angle are estimate to be better that 0.1 degree.Öğe Examination of Accuracy of Interior Positioning(Institute of Electrical and Electronics Engineers Inc., 2024) Dogan, Nezir; Bettemir, Onder HalisIndoor positioning applications have become widespread as the required sensors have become affordable. In the literature, the location accuracy obtained by using different types of sensors has been examined, but the placement geometry of the sensors is not taken into account. In order to address the stated research gap, the effect of sensor distribution on indoor location accuracy obtained by triangulation technique was examined. The effect of different placing distributions of 4 stations on the location accuracy obtained in different parts of the interior location was determined with simulation. White noise of 1 cm is added to the exact distances between the station and the measured point. Then linearized triangulation equations were solved by the least squares adjustment and location information was obtained by compensating the errors. Similar positioning accuracies were obtained when the station points were distributed evenly. However, in the analysis error values of the order of 35 cm were obtained especially in the regions close to the stations when the station points were placed on the same side of the room. As a result of this study, it was determined that the placement geometry of the station points significantly affects the location accuracy. © 2024 IEEE.Öğe Fast Converging Moment Distribution Algorithm for Structural Analysis on Smartphones(Turkish Chamber Civil Engineers, 2017) Bettemir, Onder HalisThroughout the construction, unforeseen loading combinations on the scaffolding and the temporary facilities may occur. Since the site engineers have to take quick decisions, they make intuitive decisions, which may cause failures. In this study, moment distribution method based structural algorithm, which can run on handheld devices, is proposed to assist site engineers. Conventional moment distribution method is improved to solve the frames that are free to sidesway and settlement at once. As a result, the proposed algorithm can be efficiently implemented on hand-held devices, which have limited memory and processing power. Whereby, the site engineer can analyze any construction phase real-time and immediately take sound decisions.Öğe Hybrid Genetic Algorithm with Simulated Annealing for Resource-Constrained Project Scheduling(Asce-Amer Soc Civil Engineers, 2015) Bettemir, Onder Halis; Sonmez, RifatResource-constrained project scheduling problem (RCPSP) is a very important optimization problem in construction project management. Despite the importance of the RCPSP in project scheduling and management, commercial project management software provides very limited capabilities for the RCPSP. In this paper, a hybrid strategy based on genetic algorithms, and simulated annealing is presented for the RCPSP. The strategy aims to integrate parallel search ability of genetic algorithms with fine tuning capabilities of the simulated annealing technique to achieve an efficient algorithm for the RCPSP. The proposed strategy was tested using benchmark test problems and best solutions of the state-of-the-art algorithms. A sole genetic algorithm, and seven heuristics of project management software were also included in the computational experiments. Computational results show that the proposed hybrid strategy improves convergence of sole genetic algorithm and provides a competitive alternative for the RCPSP. The computational experiments also reveal the limitations of the project management software for resource-constrained project scheduling. (C) 2014 American Society of Civil Engineers.Öğe A Memetic Algorithm for the Solution of the Resource Leveling Problem(Mdpi, 2023) Iranagh, Mehdi; Sonmez, Rifat; Atan, Tankut; Uysal, Furkan; Bettemir, Onder HalisIn this paper, we present a novel memetic algorithm (MA) for the solution of the resource leveling problem (RLP). The evolutionary framework of the MA is based on integration of a genetic algorithm and simulated annealing methods along with a resource leveling heuristic. The main objective of the proposed algorithm is to integrate complementary strengths of different optimization methods and incorporate the individual learning as a separate process for achieving a successful optimization method for the RLP. The performance of the MA is compared with the state-of-the-art leveling methods. For small instances up to 30 activities, mixed-integer linear models are presented for two leveling metrics to provide a basis for performance evaluation. The computational results indicate that the new integrated framework of the MA outperforms the state-of-the-art leveling heuristics and meta-heuristics and provides a successful method for the RLP. The limitations of popular commercial project management software are also illustrated along with the improvements achieved by the MA to reveal potential contributions of the proposed integrated framework in practice.Öğe MINIMUM-COST DESIGN OF WATER DISTRIBUTION LINE WITH DIFFERENTIAL EVOLUTION ALGORITHM(Yildiz Technical Univ, 2017) Ozdemir, Ozgur; Bettemir, Onder Halis; Firat, MahmutIn this study, a design approach which minimizes the construction and operation costs of water distribution line with differential evolution algorithm is proposed. Digital Elevation Model, monthly water demand, technical codes and unit prices of construction items are defined to optimization module in order to realize the cost optimum design. Pump, pipe diameter and type are defined as design variables. Construction cost of the design is computed by the unit price of the cost items. To determine the annual operation costs, flow is computed according to the Darcy-Weisbach equations. Pumping duration is determined and annual energy cost is computed. Net present value of the investment is computed by considering the time value of the money which is evaluated by the debt interest rate. Minimum-cost design alternative is searched by differential evolution algorithm. As a result, the best pump and pipe combination is obtained and summation of the construction and operation costs are minimized. Minimization of the sum of the investment and operation costs may provide the opportunity of significant improvement in the budget of the municipalities in the long run. Consequently, implementation of the proposed design approach will be beneficial for the local authorities.
