Project resources leveling using software agents

Different approaches to project planning and scheduling have been developed. The Operational Research (OR) approach provides two major planning techniques: CPM and PERT. Artificial Intelligence (AI) initially promoted the automatic planner concept. In order to plan a project, the automatic application of predefined operators is required. However, most domains are not so easily formalized in the form of predefined planning operators. The paper focus is on the agent-based approach to project planning and scheduling, especially in Resource Leveling issues. The authors have developed and implemented the ResourceLeveler system, an agent-based model for leveling project resources. The objective of Resource Leveler is to find a scheduling of resources similar to the optimal theoretical solution which takes into consideration all constraints stemming from the relationships between projects, activity calendars, resource calendars, resource allotment to the activities and resource availability. ResourceLeveler was developed in C# as a plug-in for Microsoft Project.project management, agent-based models, artificial intelligence, project resource leveling

Development of an Automated Multiple Material Stereolithography Machine

An automated Multiple Material Stereolithography (MMSL) machine was developed by integrating components of a 3D Systems 250/50 stereolithography (SL) machine in a separate stand-alone system and adapting them to function with additional components required for MMSL operation. We previously reported retrofitting a 250/50 SL machine with multiple vats to accommodate multiple material fabrication for building a wide variety of multi-material models (Wicker et al., 2004). In the MMSL retrofit, spatial constraints limited the multiple vats located circumferentially on a vertical rotating vat carousel to cross-sectional areas of approximately 4.5-inches by 4.5-inches. The limited build size of the retrofitted 250/50 motivated the full development of a new system with multiple material build capabilities comparable to the build envelope of the original 250/50 machine. The new MMSL machine required fabrication of a large system frame, incorporating various 250/50 components and software, and adding a variety of new components and software. By using many existing components and software, the previous engineering development of 3D Systems could be directly applied to this new technology. Components that were transferred from an existing 250/50 to the MMSL machine included the complete optical system (including the optics plate with laser, mirrors, beam expander, scanning mirrors, and focusing lens), the rim assembly (including the laser beam profilers), the associated controllers (computer system, scanning mirror controller, power supply-vat controller) and the wiring harness. In addition to the new frame, the MMSL machine required the development of a new rotating vat carousel system, platform assembly, multi-pump filling/leveling system, and a custom LabVIEW® control system to provide automated control over the MMSL process. The overall operation of the MMSL system was managed using the LabVIEW® program, which also included controlling a new vat leveling system and new linear and rotational stages, while the 3D Systems software (Buildstation 4.0) was retained for controlling the laser scanning process. As a demonstration of MMSL technology, simple multi material parts were fabricated with vertically and horizontally oriented interfaces. The fully functional MMSL system offers enormous potential for fabricating a wide variety of multiple material functional devices.Mechanical Engineerin

Matematičko modeliranje i neizrazito upravljanje mehanizmom za poravnavanje i podizanje

The moving process of a leveling and erecting mechanism is complicated, which involves six hydraulic cylinders. The research established mathematical model and optimized the moving process of the leveling and erecting mechanism. Kinematic analysis of the mechanism was accomplished. Mathematical model of the hydraulic system was established. Working scheme was designed consisting of workflow, trajectory planning, leveling strategy and control method. The mechanical, hydraulic and control models were respectively established in Pro/E, ADAMS, AMESim and Simulink software. Co-simulation was carried out to validate the designed scheme. Experiment was completed on a platform. The results of simulation and experiment indicate that the designed scheme is feasible. Fuzzy adaptive PID controller has an excellent effect in controlling the leveling and erecting mechanism.Gibanja mehanizma za poravnavanje i podizanje složeni je proces koji uključuje šest hidrauličkih cilindara. Istraživanje postavlja matematički model i optimizira proces gibanja mehanizma za poravnavanje i podizanje. Provedena je kinematička analiza mehanizma. Postavljen je matematički model hidrauličkog sustava. Radni program načinjen je uključujući tijek rada, planiranje trajektorije, strategiju poravnavanja i metodu upravljanja. Mehanički, hidraulički i upravljački modeli redom su izvedeni u Pro/E, ADAMS, AMESim i Simulink programskim paketima. Provedena je kosimulacija za validaciju načinjenog radnog programa. Eksperiment je proveden na stvarnoj platformi. Rezultati simulacije i eksperimenta ukazuju na izvedivost predloženog radnog programa. Neizraziti adaptivni PID regulator daje odličan efekt pri upravljanju mehanizma za poravnavanje i podizanje

Development Of Automatic Floor Tile Laying Machine [TH8531. E99 2007 f rb].

Proses pemasangan jubin lantai merupakan kerja penyudah yang lazimnya dilakukan secara manual. Proses ini digambarkan secara terperinci termasuk aliran kerja pemasangan jubin lantai, ketebalan mortar, corak pemasangan jubin, peralatan, kecacatan pemasangan, kos dan kadar kerja. Floor tile laying process is a finishing job usually done manually. This process is described in detail including the tile laying work flow, thinset thickness, tiles pattern, tools, tiles installation defects, costs and work rate

Numerical study on the internal flow field of a reversible turbine during continuous guide vane closing

The unsteady flow field in a reversible pump-turbine is investigated during the continuous load rejection using a 3D computational fluid dynamic analysis. Numerical calculations are carried out using the detached eddy simulation (DES) turbulence model and a new approach involving automatic mesh motion. In this way, the instability of the flow field is analyzed by continuously changing the guide vane openings from the best efficiency point (BEP). Unsteady flow characteristics are described by post-processing signals for several monitoring points including mass flow, torque, head and pressure in the frequency and time-frequency domains. The formation of vortices of different scales is observed from the origin to further enlargement and stabilization; the effect of the rotating structures on the flow passage is analyzed, and the influence of unsteady flow development on the performance of the turbine is investigated. Finally, the evolution during the period of load rejection is characterized in order to determine the hydrodynamic conditions causing the vibrations in the machine

Creation and Spatial Analysis of 3D City Modeling based on GIS Data

The 3D city model is one of the crucial topics that are still under analysis by many engineers and programmers because of the great advancements in data acquisition technologies and 3D computer graphics programming. It is one of the best visualization methods for representing reality. This paper presents different techniques for the creation and spatial analysis of 3D city modeling based on Geographical Information System (GIS) technology using free data sources. To achieve that goal, the Mansoura University campus, located in Mansoura city, Egypt, was chosen as a case study. The minimum data requirements to generate a 3D city model are the terrain, 2D spatial features such as buildings, landscape area and street networks. Moreover, building height is an important attribute in the 3D extrusion process. The main challenge during the creation process is the dearth of accurate free datasets, and the time-consuming editing. Therefore, different data sources are used in this study to evaluate their accuracy and find suitable applications which can use the generated 3D model. Meanwhile, an accurate data source obtained using the traditional survey methods is used for the validation purpose. First, the terrain was obtained from a digital elevation model (DEM) and compared with grid leveling measurements. Second, 2D data were obtained from: the manual digitization from (30 cm) high-resolution imagery, and deep learning structure algorithms to detect the 2D features automatically using an object instance segmentation model and compared the results with the total station survey observations. Different techniques are used to investigate and evaluate the accuracy of these data sources. The procedural modeling technique is applied to generate the 3D city model. TensorFlow & Keras frameworks (Python APIs) were used in this paper; moreover, global mapper, ArcGIS Pro, QGIS and CityEngine software were used. The precision metrics from the trained deep learning model were 0.78 for buildings, 0.62 for streets and 0.89 for landscape areas. Despite, the manual digitizing results are better than the results from deep learning, but the extracted features accuracy is accepted and can be used in the creation process in the cases not require a highly accurate 3D model. The flood impact scenario is simulated as an application of spatial analysis on the generated 3D city model. Doi: 10.28991/CEJ-2022-08-01-08 Full Text: PD

A REVIEW AND AN ANNOTATED BIBLIOGRAPHY OF STUDIES REGARDING IRRIGATION INSTITUTIONS, MANAGEMENT AND INVESTMENT IN ASIA

Resource /Energy Economics and Policy,

Inter-comparison and potential synergies of three methods for weather radar antenna pointing assessment

Three methods for estimation of the weather radar antenna azimuth and elevation pointing offsets are compared. Two of the methods reviewed use the known location of the sun as a reference. The first of these methods is based on an offline scan of the sun disk. The second method detects and characterizes solar interferences in operative scans. The third method consists of correlating measured ground clutter echoes with echoes simulated using a high-resolution digital elevation model. The main objectives are to review the characteristics in each case, studying their performance in actual operative conditions, and to examine the reasons for the discrepancies between the reported pointing bias estimates, with the aim of laying the groundwork for an optimized individual or combined application and interpretation of the methods. Daily pointing biases estimated through the sun-scanning procedure in a dedicated one-month, short-term campaign are the base for the intercomparison. When applied to the three weather radars operated by the Meteorological Service of Catalonia, the short-term study reveals the advantages and limitations of the methods. A one-year, long-term analysis serves to confirm and clarify the discrepancies inferred from the short-term study and highlights how the antenna position at the time of the measurement may influence the pointing bias estimates. Based on the long-term results, a combination of the two sun-based methods for detection and simultaneous quantification of the pointing bias and the system leveling error is discussed

Critical soft landing technology issues for future US space missions

A programmatic need for research and development to support parachute-based landing systems has not existed since the end of the Apollo missions in the mid-1970s. Now, a number of planned space programs require advanced landing capabilities for which the experience and technology base does not currently exist. New requirements for landing on land with controllable, gliding decelerators and for more effective impact attenuation devices justify a renewal of the landing technology development effort that existed during the Mercury, Gemini, and Apollo programs. A study was performed to evaluate the current and projected national capability in landing systems and to identify critical deficiencies in the technology base required to support the Assured Crew Return Vehicle and the Two-Way Manned Transportation System. A technology development program covering eight landing system performance issues is recommended