Computer and Smartphone Continuance Intention: A Motivational Model

This paper develops and tests a motivational model to explain the overall continuance intention to use computers and smartphones. Based on survey data from 192 undergraduate students, structural equation modeling analysis is used to report: (1) the independent effect of intrinsic motivation on the continuance intention to use computers and smartphones; (2) the independent effect of extrinsic motivation on the continuance intention to use computers but not smartphones; (3) intrinsic motivation mediating the effect of extrinsic motivation on the continuance intention to use computers; (4) the independent effect of technology cognizance on the continuance intention to use computers but not smartphones; (5) intrinsic motivation positively influencing extrinsic motivation and technology cognizance, with respect to both devices. This research contributes to an improved understanding of the independent and interrelated effects of intrinsic and extrinsic motivations to use technological devices. The findings have important implications for theory and practice regarding the overall use of technology.     

Lossless convexification of a class of optimal control problems with non-convex control constraints

We consider a class of finite time horizon optimal control problems for continuous time linear systems with a convex cost, convex state constraints and non-convex control constraints. We propose a convex relaxation of the non-convex control constraints, and prove that the optimal solution of the relaxed problem is also an optimal solution for the original problem, which is referred to as the lossless convexification of the optimal control problem. The lossless convexification enables the use of interior point methods of convex optimization to obtain globally optimal solutions of the original non-convex optimal control problem. The solution approach is demonstrated on a number of planetary soft landing optimal control problems.     

Recent developments in large‐area photomasks for display applications

One of the most critical areas in the manufacturing process for FPD panels or shadow masks for CRTs is lithography. Most existing lithography technologies require high‐quality large‐area photomasks. The requirements on these photomasks include positioning accuracy (registration) and repeatability (overlay), systematic image quality errors (“mura” or display quality), and resolution (minimum feature size). The general trend toward higher resolution and improved performance, e.g., for TFT desktop monitors, has put a strong focus on the specifications for large‐area‐display photomasks. This article intends to give an overview of the dominant issues for large‐area‐display photomasks, and illustrates differences compared with other applications. The article will also present state‐of‐the‐art methods and trends. In particular, the aspects of positioning accuracy over large areas and systematic image‐quality errors will be described. New qualitative and objective methods have been developed as means to capture systematic image‐quality errors. Results indicating that errors below 25 nm can be found early in the manufacturing process is presented, thus allowing inspection for visual effects before the actual display is completed. Positioning accuracy below 400 nm (3 sigma) over 720 × 560 mm have been achieved. These results will in the future be extended up toward 1 × 1 m for generation 4 in TFT‐LCD production.     

Model selection for convolutive ICA with an application to spatiotemporal analysis of EEG

We present a new algorithm for maximum likelihood convolutive independent component analysis (ICA) in which components are unmixed using stable autoregressive filters determined implicitly by estimating a convolutive model of the mixing process. By introducing a convolutive mixing model for the components, we show how the order of the filters in the model can be correctly detected using Bayesian model selection. We demonstrate a framework for deconvolving a subspace of independent components in electroencephalography (EEG). Initial results suggest that in some cases, convolutive mixing may be a more realistic model for EEG signals than the instantaneous ICA model.     

Implementation of high-resolution time-to-digital converter in 8-bit microcontrollers

This paper will demonstrate how a time-to-digital converter (TDC) with sub-nanosecond resolution can be implemented into an 8-bit microcontroller using so called "direct" methods. This means that a TDC is created using only five bidirectional digital input-output-pins of a microcontroller and a few passive components (two resistors, a capacitor, and a diode). We will demonstrate how a TDC for the range 1-10 μs is implemented with 0.17 ns resolution. This work will also show how to linearize the output by combining look-up tables and interpolation.     

External Memory Planar Point Location with Logarithmic Updates

Point location is an extremely well-studied problem both in internal memory models and recently also in the external memory model. In this paper, we present an I/O-efficient dynamic data structure for point location in general planar subdivisions. Our structure uses linear space to store a subdivision with N segments. Insertions and deletions of segments can be performed in amortized O(log? _B N) I/Os and queries can be answered in $O(\log_{B}^{2} N)$ I/Os in the worst-case. The previous best known linear space dynamic structure also answers queries in $O(\log_{B}^{2} N)$ I/Os, but only supports insertions in amortized $O(\log_{B}^{2} N)$ I/Os. Our structure is also considerably simpler than previous structures.     

Eliminating the effect of freezing frames on user perceptive by using a time interleaving technique

Streaming video over a wireless network faces several challenges such as high packet error rates, bandwidth variations, and delays, which could have negative effects on the video streaming and the viewer will perceive a frozen picture for certain durations due to loss of frames. In this study, we propose a Time Interleaving Robust Streaming (TIRS) technique to significantly reduce the frozen video problem and provide a satisfactory quality for the mobile viewer. This is done by reordering the streaming video frames as groups of even and odd frames. The objective of streaming the video in this way is to avoid the losses of a sequence of neighbouring frames in case of a long sequence interruption. We evaluate our approach by using a user panel and mean opinion score (MOS) measurements; where the users observe three levels of frame losses. The results show that our technique significantly improves the smoothness of the video on the mobile device in the presence of frame losses, while the transmitted data are only increased by almost 9% (due to reduced time locality).     

A variable neighborhood search approach for planning and scheduling of jobs on unrelated parallel machines

In this paper, we study a planning and scheduling problem for unrelated parallel machines. There are n jobs that have to be assigned and sequenced on m unrelated parallel machines. Each job has a weight that represents the priority of the corresponding customer order, a given due date, and a release date. An Automated Guided Vehicle is used to transport at maximum Load _max jobs into a storage space in front of the machines in a given period of time. We consider t _max consecutive periods. We are interested in minimizing the total weighted tardiness of the jobs across the periods. This measure is important when we are interested in a good on-time delivery performance. We present an appropriate mixed integer program. To solve this NP-hard problem, we develop a heuristic methodology based on decomposition and variable neighborhood search (VNS). The proposed approaches are assessed using randomly generated problem instances. We compare them with a simple heuristic based on decomposition and list scheduling using the Apparent Tardiness Cost dispatching rule. The results demonstrate that the heuristic approach based on VNS performs comparably to the mixed integer program while having reasonable solution times and outperforms the simple heuristic and a genetic algorithm (GA) from previous research.     

Stability, Growth, and Decline in Adult Life Span Development of Declarative Memory: Cross-Sectional and Longitudinal Data From a Population-Based Study.

Five-year changes in episodic and semantic memory were examined in a sample of 829 participants (35-80 years). A cohort-matched sample (N=967) was assessed to control for practice effects. For episodic memory, cross-sectional analyses indicated gradual age-related decrements, whereas the longitudinal data revealed no decrements before age 60, even when practice effects were adjusted for. Longitudinally, semantic memory showed minor increments until age 55, with smaller decrements in old age as compared with episodic memory. Cohort differences in educational attainment appear to account for the discrepancies between cross-sectional and longitudinal data. Collectively, the results show that age trajectories for episodic and semantic memory differ and underscore the need to control for cohort and retest effects in cross-sectional and longitudinal studies, respectively. (PsycINFO Database Record (c) 2010 APA, all rights reserved)