The net ecosystem exchange of carbon dioxide was measured by eddy covariance methods for 3 years in two old-growth forest sites near Santarém, Brazil. Carbon was lost in the wet season and gained in the dry season, which was opposite to the seasonal cycles of both tree growth and model predictions. The 3-year average carbon loss was 1.3 (confidence… (More)
Echo threshold variability has previously been examined using stimuli that are carefully controlled and artificial (e.g., clicks and noise bursts), while studies using speech stimuli have only reported average thresholds. To begin to understand how echo thresholds might vary among speech sounds, four syllables were selected in pairs that contrasted… (More)
We propose to adapt the techniques of state-modeling and feedback control from the discipline of control engineering to the tasks of software process modeling and software process control as they appear in software engineering. The scope of our investigation is focused on the construction phase (as per the rational unified process) as it occurs in… (More)
A. Site Description We made biometric observations and eddy covariance measurements at two sites in the Tapajós National Forest (FLONA Tapajós): near Km 67 (54°58'W, 2°51'S) and Km 83 (54°56'W, 3°3'S) of the Santarém-Cuiabá highway (BR-163), which runs along the eastern edge of the Tapajós National Forest (FLONA Tapajós). The FLONA Tapajós is located on the… (More)
We present an overview of our current work in modeling and control of the software test process under an incremental life cycle. We first discuss the modeling primitives and their interaction to form a predictive model, and then discuss the direction by which we address the problem of controlling the process.
Software Cybernetics explores the interplay between software and control. Though the concepts of software and cybernetics are well known when considered in isolation, the definition and scope of Software Cybernetics is sometimes blurred due to its novelty. A definition of Software Cybernetics and the delineation of its scope are the major goals of this… (More)
A software development process modeling framework is constructed under the formalism of state modeling. The approach interconnects instances of a general development-activity model into a composite system. Simulation results are presented, and implications for control-theoretic decision support are briefly discussed.
A data collection and grooming tool named DIG is reported. The tool allows the management of a software process to be able to extract data from a variety of project repositories, groom the data, and generate reports. The reports are aimed at assisting the management in the control of the software development process. DIG allows management to build a… (More)
A quantitative, adaptive process control technique is described using an industrially validated model of the software system test phase as concrete target to be controlled. The technique combines the use of parameter correction and model predictive control to overcome the problems induced by modeling errors, parameter estimation errors, and limits on the… (More)