Charles D. Knutson

Rapid heterogeneous ad hoc connection establishment: accelerating Bluetooth inquiry using IrDA

Bluetooth device discovery is a time-intensive phase of the Bluetooth connection-establishment procedure. In this paper we propose a technique that integrates existing IrDA technology with Bluetooth technology to improve the ad hoc connection establishment time of Bluetooth devices. We accomplish this improvement by first establishing an IrDA connection between two devices equipped with both Bluetooth and IrDA capabilities and then exchanging Bluetooth device discovery information via the established IrDA connection. As a result of this cooperative exchange, the devices are able to bypass the time-intensive Bluetooth device discovery procedure. Our research shows that IrDA-assisted Bluetooth connection establishment is up to four times faster than the normal ad hoc Bluetooth connection establishment procedure. In addition, it provides other time-savings in subsequent device selection procedures.

Enabling remote access to personal electronic medical records

The Poket Doktor is a wireless personal healthcare system that can obtain accurate patient medical information in situations where it may not otherwise be available. The system is designed to provide a flexible, scalable method of storing and communicating critical electronic medical record information using personal handheld electronic devices. The first phase of development has succeeded in: designing the architecture for a wireless, power-efficient smart card to store and communicate medical information incorporating Bluetooth wireless technology with radiofrequency identification wakeup on the smart card to enable a fast wireless connection to a healthcare providers device; and selecting a platform and creating application software for a handheld computing device used by healthcare providers. The Poket Doktor system assists medical personnel in obtaining accurate patient medical information in situations where it may not otherwise be available. In this manner, Poket Doktor technology will improve the quality of care delivered in emergency situations.

Trust negotiation for authentication and authorization in healthcare information systems

The expanding availability of health information in an electronic format is strategic for industry-wide efforts to improve the quality and reduce the cost of health care. The implementation of electronic medical record systems has been hindered by inadequate security provisions. This paper describes the use of trust negotiation as a framework for providing authentication and access control services in healthcare information systems. Trust negotiation enables two parties with no preexisting relationship to establish the trust necessary to perform sensitive transactions via the mutual disclosure of attributes contained within digital credentials. An extension of this system, surrogate trust negotiation is introduced as a way to meet the security requirements of healthcare delivery systems based on mobile computing devices and wireless communication technologies. These innovative technologies have enormous potential to improve the current state of security in healthcare information systems.

A self-adapting healthcare information infrastructure using mobile computing devices

Despite recent improvements in the gathering and sharing of patient medical information among healthcare providers, there remains a gap in the electronic medical record infrastructure. Patient data is not available in some situations, either because the infrastructure is inaccessible (as in a natural disaster) or because there is no way to link the patient to the infrastructure (e.g., the patient cannot supply necessary identification information). We describe the Poket Doktor System, an architecture that allows an individual to carry personal electronic medical information on a wireless handheld device such as a smart card, cell phone, or PDA. Medical workers can obtain this information wirelessly using handheld devices, desktop computers, network access points, etc. In this way, patients play an active role in the medical information infrastructure, resulting in a better healthcare delivery system.

Do Programming Languages Affect Productivity? A Case Study Using Data from Open Source Projects

Brooks and others long ago suggested that on average computer programmers write the same number of lines of code in a given amount of time regardless of the programming language used. We examine data collected from the CVS repositories of 9,999 open source projects hosted on SourceForge.net to test this assumption for 10 of the most popular programming languages in use in the open source community. We find that for 24 of the 45 pairwise comparisons, the programming language is a significant factor in determining the rate at which source code is written, even after accounting for variations between programmers and projects.

Impact of Programming Language Fragmentation on Developer Productivity: A Sourceforge Empirical Study

Programmers often develop software in multiple languages. In an effort to study the effects of programming language fragmentation on productivity-and ultimately on a developers problem-solving abilities-the authors present a metric, language entropy, for characterizing the distribution of a developers programming efforts across multiple programming languages. This paper presents an observational study examining the project contributions of a random sample of 500 SourceForge developers. Using a random coefficients model, the authors find a statistically alpha level of 0.001 and practically significant correlation between language entropy and the size of monthly project contributions. Results indicate that programming language fragmentation is negatively related to the total amount of code contributed by developers within SourceForge, an open source software OSS community.

Design Patterns in Software Maintenance: An Experiment Replication at Brigham Young University

In 2001 Prechelt et al. published the results of a controlled experiment in software maintenance comparing design patterns to simpler solutions. Since that time, only one replication of the experiment has been performed (published in 2004). The replication found remarkably (though not surprisingly) different results. In this paper we present the results of another replication of Prechelts experiment, conducted at Brigham Young University (BYU) in 2010. This replication was performed as part of a joint replication project hosted by the 2011 Workshop on Replication in Empirical Software Engineering Research (RESER). The data and results from this experiment are meant to be considered in connection with the results of other contributions to the joint replication project.

Inverse multiplexing in short-range multi-transport wireless communications

This paper describes a mechanism for utilizing inverse multiplexing to significantly increase the bandwidth available to short-range wireless devices. Previous work with inverse multiplexing has focused on wired networks; its implementation with short-range wireless transports introduces heterogeneity in the links, which must be taken into account. A mathematical model for an inverse multiplexing system is derived for several scheduling algorithms. Both process limited and transport limited systems are examined. The validity of this model is shown by our implementation of an inverse multiplexing layer that uses IrDa and Bluetooth transports. Concepts related to inverse multiplexing such as usage models, negotiation, quality of service, and the simultaneous use of multiple Bluetooth transports are discussed.

Report from the 1st international workshop on replication in empirical software engineering research (RESER 2010)

The RESER 2010 Workshop, held on May 4, 2010 in Cape Town, South Africa was co-located with the 32nd International Conference on Software Engineering (ICSE 2010). The workshop provided a venue in which empirical Software Engineering researchers could present and discuss the theoretical foundations and methods of replication, as well as the results of specific replicated studies.

Dynamic autonomous transport selection in heterogeneous wireless environments

In this paper, we introduce quality of transport (QoT), an architecture for synergistically and autonomously managing session-layer protocol access to multiple transports in heterogeneous wireless environments. We present an overview of the QoT architecture including: 1) transport discovery, 2) service discovery, 3) object exchange, 4) transport switching, and 5) intelligent transport selection. Preliminary successes with our design and implementation of QoT suggest that dynamic intelligent autonomous transport switching can help to optimize user experience and session layer performance in multi-transport environments.