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71.
Many organisations suffer from a self-inflicted wound – they attempt to do too much! As a result, nothing is done well and profits suffer. Our article addresses this problem by suggesting that managers should focus on a subset of their current initiatives – a subset selected to maximise returns without overstraining resources. We address the following issues: What are the symptoms of work overload? How does an excessive workload adversely impact the bottom line? How can managers determine the throughput capacity of their organisation? What can be done to address the problem of excessive workload? Many, if not most, organisations attempt to operate beyond their capacity, with the result that inefficiencies abound, deadlines are missed and profitability drops. Based on research and consulting experience in many companies, our paper explains the basic concepts of ‘the 25/25’ approach to project portfolio management – an approach designed to increase profitability by concentrating only on the work that is essential to the survival and profitability of the organisation. The approach has been successfully applied to dozens of public and private sector organisations companies.  相似文献   
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73.
To automate the harvesting of melons, a mobile Cartesian robot is developed that traverses at a constant velocity over a row of precut melons whose global coordinates are known. The motion planner is programmed to have the robot harvest as many melons as possible. Numerous simulations of the robot over a field with different sets of randomly distributed melons resulted in nearly identical percentages of melons harvested. This result holds true over a wide range of robot dimensions, motor capabilities, velocities and melon distributions. Using probabilistic methods, we derive these results by modelling the robotic harvesting procedure as a stochastic process. In this simplified model, a harvest ratio is predicted analytically using Poisson and geometric distributions. Further analysis demonstrates that this model of robotic harvesting is an example of an infinite length Markov chain. Applying the mathematical tools of Markov processes to our model yields a formula for the harvest percentage that is in strong agreement with the results of the simulation. The significance of the approach is demonstrated in two of its applications: to select the most efficient actuators for maximal melon harvesting and determine the set of optimal velocities along a row of melons of varying densities.  相似文献   
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75.
Manipulation and analysis of single cells is the next frontier in understanding processes that control the function and fate of cells. Herein we describe a single-cell injection platform based on nanopipettes. The system uses scanning microscopy techniques to detect cell surfaces, and voltage pulses to deliver molecules into individual cells. As a proof of concept, we injected adherent mammalian cells with fluorescent dyes.  相似文献   
76.
The neuroimaging of hydrocephalus from the perspective of the pediatric neurosurgeon is discussed. Processes with new developments in therapy and imaging are described, including congenital causes of hydrocephalus, unilateral hydrocephalus, trapped fourth ventricle, and benign external hydrocephalus.  相似文献   
77.
This paper presents a general disruption management approach for a two-stage production and inventory control system. A penalty cost for deviations of the new plan from the original plan is incorporated and the concept of a disruption recovery time window is introduced. We define two classes of problems: one with fixed setup epochs and another with flexible setup epochs. With linear or quadratic penalty functions for production/ordering quantity change and fixed setup epochs, the best recovery plan is obtained by solving a quadratic mathematical programming problem. With convex penalty functions for quantity changes and flexible setup epochs, it is shown that the second stage orders have identical order quantities within each production cycle. Therefore, in a lot-for-lot system, the ordering and production quantities for both stages are the same. As a special case, we consider disruption recovery problems with short time windows spanning one or two production cycles. We also discuss solution procedures for both major and minor disruption problems and give an extension for the case of multiple retailers. Throughout the paper managerial insights are presented that indicate how a company should respond to various types of disruptions during its operations.  相似文献   
78.
We propose a goal programming framework that aims at automating e-commerce transactions. This framework consists of three basic layers: deal definition—defining the deal’s parameters and associated constraints (e.g., item, price, delivery dates); deal manipulation—a collection of procedures for shaping deals to attain desired goals (e.g., earliest delivery and minimum price) and an applications layer that employs these procedures within some negotiations settings (e.g., an auction-related application presents a “better offer” while bidding on a contract). Our proposed foundation is rich enough to support a wide array of applications ranging from 1-1 and 1-n negotiations (auctions) to deal valuation and deal splitting. Whereas the techniques are appropriate to a multitude of settings, we shall mainly present them in the context of business-to-business (B2B) commerce where we see the greatest short term benefits. O. Shmueli’s work is partially supported by the Fund for the Promotion of Research at the Technion.  相似文献   
79.
The speed with which global high‐technology markets evolve makes companies recognize that an effective innovation process is the best way to guarantee competitiveness. However, when (medium‐sized) companies then wish to set up a corporate entrepreneurship function to enhance business development processes, they can find little material available in literature to assist in such processes. In this article we have described a guideline and some backgrounds for creating a corporate entrepreneurship function to realize business development in a high‐tech context.  相似文献   
80.
The importance of water on molecular ion structuring and charging mechanism of solid interfaces in room temperature ionic liquid (RTIL) is unclear and has been largely ignored. Water may alter structures, charging characteristics, and hence performance at electrified solid/RTIL interfaces and is utilized in various fields including energy storage, conversion, or catalysis. Here, atomic force microscopy and surface forces apparatus experiments are utilized to directly measure how water alters the interfacial structuring and charging characteristics of [C2mim][Tf2N] on mica and electrified gold surfaces. On hydrophilic and ionophobic mica surfaces, water‐saturated [C2mim][Tf2N] dissolves surface‐bound cations, which leads to high surface charging and strong layering. In contrast, layering of dry RTIL at weakly charged mica surfaces is weakly structured. At electrified, hydrophobic, and ionophilic gold electrodes, significant water effects are found only at positive applied electrochemical potentials. Here, the influence of water is limited to interactions within the RTIL layers, and is not related to a direct electrosorption of water on the polarized electrode. More generally, the results suggest that effects of water on interfacial structuring of RTIL strongly depend on both (1) surface charging mechanism and (2) interfacial wetting properties. This may greatly impact utilization/design of RTILs and surfaces for interface‐dominated processes.  相似文献   
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