Minimum Makespan Multi-vehicle Dial-a-Ride

Dial a ride problems consist of a metric space (denoting travel time between vertices) and a set of m objects represented as source-destination pairs, where each object requires to be moved from its source to destination vertex. We consider the multi-vehicle Dial a ride problem, with each vehicle having capacity k and its own depot-vertex, where the objective is to minimize the maximum completion time (makespan) of the vehicles. We study the "preemptive" version of the problem, where an object may be left at intermediate vertices and transported by more than one vehicle, while being moved from source to destination. Our main results are an O(log^3 n)-approximation algorithm for preemptive multi-vehicle Dial a ride, and an improved O(log t)-approximation for its special case when there is no capacity constraint. We also show that the approximation ratios improve by a log-factor when the underlying metric is induced by a fixed-minor-free graph.Comment: 22 pages, 1 figure. Preliminary version appeared in ESA 200

Improved head-controlled TV system produces high-quality remote image

Manipulator operator uses an improved resolution tv camera/monitor positioning system to view the remote handling and processing of reactive, flammable, explosive, or contaminated materials. The pan and tilt motions of the camera and monitor are slaved to follow the corresponding motions of the operators head

Building Leadership Capacities Through Course Development Planning at a Conventional University

This Organizational Improvement Plan (OIP) looks at reducing the resistance found when faculty members are asked to use a systematic plan for online course development. The course development plan is a framework that is built around the concept of “backwards design” (Wiggins & McTighe, 2005). Backwards design makes all items congruent—the assessments to the activities, activities to the instructions, and instructions to topics and learning outcomes. The literature review within the context of this OIP, found that course development planning lacks flexibility, creates anxieties with faculty members, is time consuming, and organizational faculty development support is limited and/or inadequate. To address these concerns, Schein’s (2010) organizational culture model, consisting of three-stages and a primary driver on “culture” was introduced. In terms of finding a solution, four were proposed and one, enabling a “proof of concept” was introduced including the use of servant leadership as the selected approach to help achieve this new organizational state. Finally, a change plan based on the Plan, Do, Study, Act (PDSA) model (The W. Edwards Deming Institute, 2016) was presented that addressed the transition to the new state, goals, monitoring of the plan, and ethical considerations. Communities of Practice (CoP) (Lave & Wenger, 1991) and Professional Learning Communities (Abbott, Guisbond, Levy, & Sommerfeld, 2014; DuFour & Eaker, 2009) were also considered important concepts in helping to move this change plan towards success. Abstract This Organizational Improvement Plan (OIP) looks at reducing the resistance found when faculty members are asked to use a systematic plan for online course development. The course development plan is a framework that is built around the concept of “backwards design” (Wiggins & McTighe, 2005). Backwards design makes all items congruent—the assessments to the activities, activities to the instructions, and instructions to topics and learning outcomes. The literature review within the context of this OIP, found that course development planning lacks flexibility, creates anxieties with faculty members, is time consuming, and organizational faculty development support is limited and/or inadequate. To address these concerns, Schein’s (2010) organizational culture model, consisting of three-stages and a primary driver on “culture” was introduced. In terms of finding a solution, four were proposed and one, enabling a “proof of concept” was introduced including the use of transactional, transformational, and servant leadership as the selected approaches to help achieve this new organizational state. Finally, a change plan based on the Plan, Do, Study, Act (PDSA) model (The W. Edwards Deming Institute, 2016) was presented that addressed the transition to the new state, goals, monitoring of the plan, and ethical considerations. Communities of Practice (CoP) (Lave & Wenger, 1991) and Professional Learning Communities (Abbott, Guisbond, Levy, & Sommerfeld, 2014; DuFour & Eaker, 2009) were also considered important concepts in helping to move this change plan towards success

Improved electromechanical master-slave manipulator

Electric master-slave manipulator uses force multiplication and allows the operator to remotely control the slave arm. Both the master and slave arms execute seven distinct motions by a specially designed force-reflecting servo having a one to one correspondence between the motion at the master and slave

Effect of magnetic field on the phase transition in a dusty plasma

The formation of self-consistent crystalline structure is a well-known phenomenon in complex plasmas. In most experiments the pressure and rf power are the main controlling parameters in determining the phase of the system. We have studied the effect of externally applied magnetic field on the configuration of plasma crystals, suspended in the sheath of a radio-frequency discharge using the Magnetized Dusty Plasma Experiment (MDPX) device. Experiments are performed at a fixed pressure and rf power where a crystalline structure is formed within a confining ring. The magnetic field is then increased from 0 to 1.28 T. We report on the breakdown of the crystalline structure with increasing magnetic field. The magnetic field affects the dynamics of the plasma particles and first leads to a rotation of the crystal. At higher magnetic field, there is a radial variation (shear) in the angular velocity of the moving particles which we believe leads to the melting of the crystal. This melting is confirmed by evaluating the variation of the pair correlation function as a function of magnetic field.Comment: 9 pages, 5 figure

But Not Both:The Exclusive Disjunction in Qualitative Comparative Analysis (QCA)

The application of Boolean logic using Qualitative Comparative Analysis (QCA) is becoming more frequent in political science but is still in its relative infancy. Boolean ‘AND’ and ‘OR’ are used to express and simplify combinations of necessary and sufficient conditions. This paper draws out a distinction overlooked by the QCA literature: the difference between inclusive- and exclusive-or (OR and XOR). It demonstrates that many scholars who have used the Boolean OR in fact mean XOR, discusses the implications of this confusion and explains the applications of XOR to QCA. Although XOR can be expressed in terms of OR and AND, explicit use of XOR has several advantages: it mirrors natural language closely, extends our understanding of equifinality and deals with mutually exclusive clusters of sufficiency conditions. XOR deserves explicit treatment within QCA because it emphasizes precisely the values that make QCA attractive to political scientists: contextualization, confounding variables, and multiple and conjunctural causation