Thermoelectric temperature control device for vapor pressure measurements

The static method of measuring equilibrium vapor pressure requires locating the sample at the coldest part of the apparatus to avoid errors due to evaporation and recondensation elsewhere. This paper describes a device that can hold the sample 1 K below the temperature of the surrounding air without a liquid bath. It comprises a pair of thermoelectric elements and two thermometers attached to an insulated aluminum block. The device can operate as high as 200?°C while controlling the sample with a precision of 0.02 K; below 110?°C, the precision is 2 mK. Also described is a method to measure the small temperature offset due to heat flow between the sample and the surrounding aluminum block. The uncertainty due to the offset is small compared to the 6 mK uncertainty due to the thermometer.     

Diffraction contrast STEM of dislocations: imaging and simulations

The application of scanning transmission electron microscopy (STEM) to crystalline defect analysis has been extended to dislocations. The present contribution highlights the use of STEM on two oppositely signed sets of near-screw dislocations in hcp α-Ti with 6wt% Al in solid solution. In addition to common systematic row diffraction conditions, other configurations such as zone axis and 3g imaging are explored, and appear to be very useful not only for defect analysis, but for general defect observation. It is demonstrated that conventional TEM rules for diffraction contrast such as g·b and g·R are applicable in STEM. Experimental and computational micrographs of dislocations imaged in the aforementioned modes are presented.     

DB2 Universal Database: A Case Study of a Successful User-Centered Design Program

This case study describes the application of user-centered design (UCD) principles to the development of a complex middleware software product-IBM's DB2(r) Universal Database. Motivated by trade press reviews highlighting ease-of-use problems, a multisite development team utilized IBM UCD to transform ease of use into a featured product attribute. This case study describes the initial application of UCD to DB21 and the positive business results that followed: critical acclaim, increased marketshare and user satisfaction, and increased support and adoption of UCD across the IBM database product family. Although ease-of-use objectives, target markets, and human factors practitioners' roles have evolved over 6 years and multiple versions of the product, DB2 continues to achieve positive results with UCD. In addition to the flexibility of the UCD methodology, other factors that influenced DB2's success included management support, resource commitment, cross-site communication and collaboration, detailed product specifications, and a focus on supporting user tasks.     

Building Trust and Cooperation through Technology Adaptation in Virtual Teams: Empirical Field Evidence

Abstract

This article reports findings of a study of how leaders of virtual information systems development teams improve team trust and cooperation by managing adaptation of information and communications tools. Results indicate how Theory X (command and control) and Theory Y (facilitate and support) styles of leadership enable and hinder effective outcomes.     

Upgrading the Computer

Abstract

Until recently, hardware was upgraded simply by ordering a larger, faster, more expensive computer. Now, upgrading a system is more complex but potentially more rewarding. The complexity results from the many alternative approaches available, the advent of distributed processing with its networking implications, the proliferation of microcomputers and office systems and the potential need to integrate them, and the options available for obtaining equipment. An understanding of an organization's needs and careful planning can make an equipment upgrade successful.     

Beyond Transactional Systems

Although most organizations realize the need to shift the emphasis in systems development from transactional systems to tactical and strategic systems, they are often reluctant or unable to do so. This column examines the reasons for this and discusses how MIS managers can motivate both users and senior managers to develop these systems.     

A Multicast-Enabled Delivery Framework for QoE Assurance of Over-The-Top Services in Multimedia Access Networks

Over-The-Top (OTT) video services are becoming more and more important in today’s broadband access networks. While original OTT services only offered short duration medium quality videos, more recently, premium content such as high definition full feature movies and live video are offered as well. For operators, who see the potential in providing Quality of Experience (QoE) assurance for an increased revenue, this introduces important new network management challenges. Traditional network management paradigms are often not suited for ensuring QoE guarantees as the provider does not have any control on the content’s origin. In this article, we focus on the management of an OTT-based video service. We present a loosely coupled architecture that can be seamlessly integrated into an existing OTT-based video delivery architecture. The framework has the goal of resolving the network bottleneck that might occur from high peaks in the requests for OTT video services. The proposed approach groups the existing Hypertext Transfer Protocol (HTTP) based video connections to be multicasted over an access network’s bottleneck and then splits them again to reconstruct the original HTTP connections. A prototype of this architecture is presented, which includes the caching of videos and incorporates retransmission schemes to ensure robust transmission. Furthermore, an autonomic algorithm is presented that allows to intelligently select which OTT videos need to be multicasted by making a remote assessment of the cache state to predict the future availability of content. The approach was evaluated through both simulation and large scale emulation and shows a significant gain in scalability of the prototype compared to a traditional video delivery architecture.     

STRATEGIC PLANNING The MIS Strategic Planning Process

Abstract

A large portion of the literature about business and information systems is written at the grand, strategic level. That is certainly the case for the first two books reviewed in this column. One deals with the broad implications of the shift of routine IT work to Asia and the potential for this shift to expand into development and concepts. The other presents a framework for ameliorating IT risk. The third book is concerned with the nitty gritty of the little decisions, made over and over, in day-to-day operations. The focus is on ways of improving and automating these decisions to gain strategic advantage. And, as you would expect, this third book is much longer and much more detailed than the first two.     

Smart‐Home Interface Design: Layout Organization Adapted to Americans' and Koreans' Cognitive Styles

Increases in the number of household appliances and devices with RFID tags have created a need for efficient organization of smart‐home interfaces in consideration of residents. Previous studies of information‐grouping and cultural‐differences in cognitive style on performance have yielded mixed results. Gender has not typically been considered, nor have subjective preferences been measured. We tested four participant groups (American and Korean males and females) and two interface groupings (functional and spatial). Participants performed tasks that required locating controls for specific devices/functions, after which they rated the interfaces on several scales. American males preferred the functional organization, but Koreans and American females tended to prefer the spatial organization. The results are consistent with Koreans' preference for thematic‐structure and the view that men's and women's cognitive styles differ in masculine/individualistic cultures (U.S.) but not in feminine/collectivistic cultures (Korea). Potential applications include physical (e.g., power and wall‐mounted switches) and virtual interactions (e.g., remote controls, GUI/Web/Phone). © 2012 Wiley Periodicals, Inc.