摘要 :
For approximately five years, the Last Planner System ? has been used more and more in Spain, due to the improvement that its use produces in the productivity of the construction, reaching, with its use, better results in the achi...
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For approximately five years, the Last Planner System ? has been used more and more in Spain, due to the improvement that its use produces in the productivity of the construction, reaching, with its use, better results in the achievement of the objectives of: Cost, time and quality of the projects. But still it is necessary its knowledge and diffusion so the application of this System will be normal in all our works. It was Professors Glenn Ballard and Greg Howell of the University of Berkeley in California, United States, who in the early 90s of the last Century investigated a form of planning of the work that, within the Lean Construction philosophy, were more appropriate with the special characteristics of the construction process. Lean Construction contributes with numerous associate techniques to improve the constructive process, and one of them is Last Planner System ?. In this paper we will do a quick revision of the state of art related with Planification Methodologies which have been used in construction during last and present centuries, to conclude that Last Planner System ? represents a considerable improvement in relation with previous Systems. It is an opinion and reveal paper to promote the knowledge and use of this System in Spanish Construction with greatest interest.
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With Last Planner, obtained from Lean Construction (Construction without losses), where there will be realized an implementation of this system to a subcontract of a construction company, to strengthen deficient aspects that debil...
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With Last Planner, obtained from Lean Construction (Construction without losses), where there will be realized an implementation of this system to a subcontract of a construction company, to strengthen deficient aspects that debilitate the performance of the fulfillment of the aims of the company. It realized a training and implementation of Last Planner System to a subcontract, obtaining excellent results with respect to meeting work commitments acquired by him, efficiency in finding, eliminating or diminishing the reasons by which the activities are not delivered in the approved period, learning in planning own work and the consequence of overcoming the variability and uncertainties of the construction industry. Finally it was concluded that, although applicable to such subcontract showed favorable results, not impact on the overall performance of the construction company that work, however it is projected that the system be applied massively to subcontracts of a work of construction, significant improvement can be discerned, undermining the main reason why the construction did not meet their goals, the performance of subcontracts.
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In order to understand passenger needs regarding multimodal journey planners a framework of aspects was created. The passengers were divided into user groups, so that all the different expectations could be represented. To recogni...
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In order to understand passenger needs regarding multimodal journey planners a framework of aspects was created. The passengers were divided into user groups, so that all the different expectations could be represented. To recognize realistic needs of the user groups a survey was composed about the importance of the aspects. Having the results of the survey a statistical analysis was performed. Although, big differences were expected among the user groups, according to the survey's results no significant differences could be detected concerning the main aspects. But considering single aspects many differences turned out, which are discussed briefly. The obtained values for the single aspects were weighted according to the general preferences of the users and were compared to the original values. As a result the most important main aspects are route planning (33%) and handled data (31%), while booking and payment (16%), comfort service information (10%), supplementary information (10%) have lower relevance. Finally the ranking of different multimodal journey planners were performed. The evaluation provides information for the journey planner operators about possible directions of development based on real user needs.
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Biopsies involve taking samples from living tissue using a biopsy needle. In current clinical practice they are a first mandatory step before any further medical actions are planned. Performing a biopsy on a deep seated brain tumo...
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Biopsies involve taking samples from living tissue using a biopsy needle. In current clinical practice they are a first mandatory step before any further medical actions are planned. Performing a biopsy on a deep seated brain tumor requires considerable time for establishing and validating the desired biopsy needle pathway to avoid damage. In this paper, we present a system for the visualization, analysis, and validation of biopsy needle pathways. Our system uses a multi-level approach for identifying stable needle placements which minimize the risk of hitting blood vessels. This is one of the major dangers in this type of intervention. Our approach helps in identifying and visualizing the point on the pathway that is closest to a surrounding blood vessel, requiring a closer inspection by the neurosurgeon. An evaluation by medical experts is performed to demonstrate the utility of our system.
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This paper reports a feedback-based manoeuvre planning approach for automated nonprehensile selective micromanipulation of large, microscopic biological objects (～100μm). We employ ferromagnetic micro-particles as microrobots ac...
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This paper reports a feedback-based manoeuvre planning approach for automated nonprehensile selective micromanipulation of large, microscopic biological objects (～100μm). We employ ferromagnetic micro-particles as microrobots actuated via a global magnetic field produced by electromagnetic coils placed in quadrupole configuration. The microrobot motion is programmed to push the target object to the goal location. We employ a three-step approach comprising: (a) generate a collision-free optimal path between the initial and the commanded goal location, (b) generate a manoeuvre planning algorithm that invokes one of the three motion manoeuvres, namely, ‘approach’, ‘push’, and ‘align’ depending upon the instantaneous locations of the microrobot, target object, and the desired waypoint, and (c) deploy a simple proportional controller that determines the currents required in the electromagnetic coils that can produce a suitable magnetic field for executing the manoeuvre invoked by the manoeuvre planner. This paper reports a number of validation experiments conducted on both zebrafish, i.e., Danio rerio embryos and silica beads as target objects. We envisage that the developed inexpensive approach can be useful in robotic manipulation of biological objects with sizes in hundreds of microns including large biological cells, polyploid giant cancer cells (PGCC), multicellular spheroids, Dictyostelium slug, human oocytes, and autophagy candidates. We also believe that functionalizing the microrobots with living cells or suitable chemicals will make it possible to perform on-chip biological experiments in future.
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While our decadal planners are considering formal coursework requirements for Australian PhD programs in the mathematical sciences, doubts about the value of PhDs per se are being raised in government.
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Efficient and reliable tools that help us to manage
and plan our daily activities are an essential part of our busy
life. Trip planner is one of the tools that not only helps to plan
an unfamiliar journey but also is important ...
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Efficient and reliable tools that help us to manage
and plan our daily activities are an essential part of our busy
life. Trip planner is one of the tools that not only helps to plan
an unfamiliar journey but also is important for reliable planning
of the dynamic daily travel. Numerous trip planners from
bike apps to sophisticated airline based intercontinental travel
are developed and implemented. Availability of a Btruly
intermodal^ trip planner with real time information is the need
of the hour, and is something which is currently not Btruly^
available. This paper presents the key architecture requirements
for the development of the intermodal trip planners. It
also discuss about the challenges in the development and implementation
of a truly multimodal trip planner.
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This paper proposes a temporal path planner (TPP) in an integrated path planner (IPP), which is composed of a global path planner (GPP) and a local path planner (LPP). The LPPs are able to avoid obstacles within the range of built...
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This paper proposes a temporal path planner (TPP) in an integrated path planner (IPP), which is composed of a global path planner (GPP) and a local path planner (LPP). The LPPs are able to avoid obstacles within the range of built-in sensors, but it is difficult to generate an efficient path outside of the sensor range and to avoid getting stuck in cul-de-sacs. The GPPs can generate efficient global paths in a target region using a built-in global map, but the accuracy is not always sufficient to avoid collision, and the performance is highly dependent upon the accuracy of the global map. A simple combination of a GPP and an LPP causes path mismatch problems due to inconsistencies between the information acquired from the local sensors and the information from the preliminary global map. When erroneous global waypoints caused by low-accuracy information or a change of terrain are given to the unmanned ground vehicle (UGV), the proposed method attempts to find a detour via the original global waypoints located nearby to accomplish successful navigation using only sensory information and the global waypoint sequence from the GPP result provided initially. The TPP includes three sub-algorithms: the Temporal Waypoint Reviser (TWR), the Temporal Map Reviser (TMR) and the Temporal Distance-Heuristic-based Decision (TDHD). The simulation results demonstrate that the performance of the TPP outperforms other planners.
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This paper proposes a temporal path planner (TPP) in an integrated path planner (IPP), which is composed of a global path planner (GPP) and a local path planner (LPP). The LPPs are able to avoid obstacles within the range of built...
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This paper proposes a temporal path planner (TPP) in an integrated path planner (IPP), which is composed of a global path planner (GPP) and a local path planner (LPP). The LPPs are able to avoid obstacles within the range of built-in sensors, but it is difficult to generate an efficient path outside of the sensor range and to avoid getting stuck in cul-de-sacs. The GPPs can generate efficient global paths in a target region using a built-in global map, but the accuracy is not always sufficient to avoid collision, and the performance is highly dependent upon the accuracy of the global map. A simple combination of a GPP and an LPP causes path mismatch problems due to inconsistencies between the information acquired from the local sensors and the information from the preliminary global map. When erroneous global waypoints caused by low-accuracy information or a change of terrain are given to the unmanned ground vehicle (UGV), the proposed method attempts to find a detour via the original global waypoints located nearby to accomplish successful navigation using only sensory information and the global waypoint sequence from the GPP result provided initially. The TPP includes three subalgorithms: the Temporal Waypoint Reviser (TWR), the Temporal Map Reviser (TMR) and the Temporal Distance-Heuristic-based Decision (TDHD). The simulation results demonstrate that the performance of the TPP outperforms other planners.
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A When mission planners talk about decommissioning a spacecraft, they first need to consider whether they would like to communicate with it later. If so, the key is to design a hibernation or safe mode that allows the craft to spe...
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A When mission planners talk about decommissioning a spacecraft, they first need to consider whether they would like to communicate with it later. If so, the key is to design a hibernation or safe mode that allows the craft to spend long time spans on its own without maintenance from the ground. This requires making sure we always know where it is in its orbit and that its sensor calibration curves are valid for long periods. We also need to make sure the spacecraft's orbit is safe for the time it will be in "storage." Finally, we configure it to receive commands (usually through its Low Gain Antenna, or LGA) with the widest possible pattern. The Low Gain Antennas generally have a wide coverage pattern, while the useful beam of a High Gain Antenna is generally fairly narrow. Configuring the spacecraft to receive commands through its LGA ensures that commands can be received by the spacecraft over a relatively wide range of pointing attitudes, and we turn off the transmitter, allowing mission controllers to wake up the spacecraft for possible future use.
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