Solving Project Delays and Abandonment Using Hybrid Resource-Constrained Project Scheduling Models

Resource-constrained project scheduling models either the single-mode or the multi-mode case finds minimum schedule that minimizes the completion time of a project with constant per period renewable resource. That the level of provided resources, each period must be constant, does not reflect a real-life situation and hence makes these models inappropriate for solving project delays and abandonment. We present a Hybrid resource-constrained project scheduling problem (Hybrid RCPSP), the single-mode case and the multi-mode case for solving delays and abandonment of projects. These models are combination of the existing single-mode and multi-mode RCPSP models with some added assumptions. Our method essentially formulates the network project as a Hybrid RCPSP (single-mode or the multi-mode) and then finds the minimal schedule that minimizes the completion time of the project using priority rule based scheduling technique, while the level of the renewable resource availability varies. The idea is that if a completion time of the project can be minimized then, that project cannot be delayed or abandoned. We performed our method on a real-life building construction project (a fenced three-bedroom bungalow), a fictitious single-mode and multi-mode network projects. Our result of the real-life building construction project, show that to solve project delays and abandonment, the level of per period available resource should vary and our result of the fictitious Single-Mode and Multi-mode RCPSP show that no matter how small (even at zero level in some time periods), the per period amount and how long the length of the period, the projects will not be delayed or even abandone

Geotechnical Application for the Design and Estimation of Amata-Lekwesi, Nigeria Open Mine

The need for a proper understanding of the subsurface geology of a place and the depositional pattern of what is to be mined is very important in establishing its mining trend especially if such deposits are not exposed at the surface. Eleven borings were made in the quarry pit and around the surrounding berm to depths of 25 meters at a sampling interval of 1.0m into the intrusive rock bodies using Slanzi rotary diamond coring rig. The depth range of the boreholes varies from 15.0 meters to 25.0 meters. Rock/Soil samples obtained from borings were subjected to both visual field examination and laboratory tests/analyses to guide in designing a mine system that is based on the geology, trending pattern and geotechnical properties of the rocks. The intrusive was observed to trend in the east-west orientation. However, north-south trends were also observed at certain sections of the mine/quarry. The values of the plunges of the intrusive were observed to be between 2o and 6o at the northern southern segments. The average thickness of the intrusive bodies varies from 11.20m for the surrounding bench area to 20.00m in the pit. This observed thickness of rock mass covers an area of approximately 81,750 m2, made up of 29,500 m2 for the floor of the quarry and 52,250 m2 for the surrounding bench. The area of the surrounding berm and the pit floor area are  52,250 m2 and 29,500m2 respectively. A total reserve tonnage of 3,874,000 was obtained. Keywords: Geotechnical, Mining design, intrusive body, Slanzi rotary diamond coring rig, Quarry, Trend, Plung

Recombinant Human Interleukin-11 Treatment Enhances Collateral Vessel Growth After Femoral Artery Ligation

We investigated the role of recombinant human interleukin-11 (rhIL-11) on in vivo mobilization of CD34+/VEGFR2+ mononuclear cells and collateral vessel remodeling in mouse model of hindlimb ischemia

Perceptual judgment and saccadic behavior in a spatial distortion with briefly presented stimuli.

When observers are asked to localize the peripheral position of a small probe with respect to the mid-position of a spatially extended comparison stimulus, they tend to judge the probe as being more peripheral than the mid-position of the comparison stimulus. This relative mislocalization seems to emerge from differences in absolute localization, that is the comparison stimulus is localized more towards the fovea than the probe. The present study compared saccadic behaviour and relative localization judgements in three experiments and determined the quantitative relationship between both measures. The results showed corresponding effects in localization errors and saccadic behaviour. Moreover, it was possible to estimate the amount of the relative mislocalization by means of the saccadic amplitude

Sensory Processing of Motor Inaccuracy Depends on Previously Performed Movement and on Subsequent Motor Corrections: A Study of the Saccadic System

When goal-directed movements are inaccurate, two responses are generated by the brain: a fast motor correction toward the target and an adaptive motor recalibration developing progressively across subsequent trials. For the saccadic system, there is a clear dissociation between the fast motor correction (corrective saccade production) and the adaptive motor recalibration (primary saccade modification). Error signals used to trigger corrective saccades and to induce adaptation are based on post-saccadic visual feedback. The goal of this study was to determine if similar or different error signals are involved in saccadic adaptation and in corrective saccade generation. Saccadic accuracy was experimentally altered by systematically displacing the visual target during motor execution. Post-saccadic error signals were studied by manipulating visual information in two ways. First, the duration of the displaced target after primary saccade termination was set at 15, 50, 100 or 800 ms in different adaptation sessions. Second, in some sessions, the displaced target was followed by a visual mask that interfered with visual processing. Because they rely on different mechanisms, the adaptation of reactive saccades and the adaptation of voluntary saccades were both evaluated. We found that saccadic adaptation and corrective saccade production were both affected by the manipulations of post-saccadic visual information, but in different ways. This first finding suggests that different types of error signal processing are involved in the induction of these two motor corrections. Interestingly, voluntary saccades required a longer duration of post-saccadic target presentation to reach the same amount of adaptation as reactive saccades. Finally, the visual mask interfered with the production of corrective saccades only during the voluntary saccades adaptation task. These last observations suggest that post-saccadic perception depends on the previously performed action and that the differences between saccade categories of motor correction and adaptation occur at an early level of visual processing

Identification of RhoGAP22 as an Akt-Dependent Regulator of Cell Motility in Response to Insulin▿‡

Insulin exerts many of its metabolic actions via the canonical phosphatidylinositide 3 kinase (PI3K)/Akt pathway, leading to phosphorylation and 14-3-3 binding of key metabolic targets. We previously identified a GTPase-activating protein (GAP) for Rac1 called RhoGAP22 as an insulin-responsive 14-3-3 binding protein. Insulin increased 14-3-3 binding to RhoGAP22 fourfold, and this effect was PI3K dependent. We identified two insulin-responsive 14-3-3 binding sites (pSer16 and pSer395) within RhoGAP22, and mutagenesis studies revealed a complex interplay between the phosphorylation at these two sites. Mutating Ser16 to alanine blocked 14-3-3 binding to RhoGAP22 in vivo, and phosphorylation at Ser16 was mediated by the kinase Akt. Overexpression of a mutant RhoGAP22 that was unable to bind 14-3-3 reduced cell motility in NIH-3T3 fibroblasts, and this effect was dependent on a functional GAP domain. Mutation of the catalytic arginine of the GAP domain of RhoGAP22 potentiated growth factor-stimulated Rac1 GTP loading. We propose that insulin and possibly growth factors such as platelet-derived growth factor may play a novel role in regulating cell migration and motility via the Akt-dependent phosphorylation of RhoGAP22, leading to modulation of Rac1 activity