Load prediction method for heat and electricity demand in buildings for the purpose of planning for mixed energy distribution systems

Energy planning for mixed energy distribution systems is important to increase the flexibility in the regional and national energy systems. Expected maximum loads, load profiles and yearly energy demands, all divided into heat and electricity purposes, are important input parameters to plan for the most economical, technical and environmental optimal energy distribution system for a planning area. First, this article presents a load prediction method which estimates heat and electricity load profiles for various building categories. The method is based on statistical analyses of hourly simultaneous measured district heat and electricity consumption in several buildings, as well as background information of the measured buildings. The heat load model is based on regression analyses, whereas the electricity load model is based on various statistical distributions. Second, a method for load aggregation based on the building categories’ load profiles is presented to estimate the maximum load demands, yearly load profiles, load duration profiles and yearly energy demands, all divided into heat and electricity purposes, for a planning area.     

Radiation characteristics of strip loaded hollow dielectric E-planesectoral horn antennas

The authors report the development of a novel E-plane sectoral horn. A metallic strip of optimum length loaded on the horn is capable of giving symmetric patterns both in the E and H-planes with low sidelobe levels     

Stabilized rapidly convergent 18-degrees-of-freedom flat shell triangular element

A rank-sufficient flat triangular shell element with drilling degrees-of-freedom is described. A variational basis for this element has been provided by a three-field variational principle with relaxed interelement compatibility and traction continuity conditions. A generalized spurious mode control procedure has been developed in order to stabilize zero energy kinematical modes. Excellent performance has been found in an obstacle course and buckling problems.     

Urinary N-acetyl-beta-D-glucosaminidase in the prediction of preeclampsia and pregnancy-induced hypertension

Urinary N-acetyl-beta-D-glucosaminidase was estimated in 109 primigravidas and the level correlated with the subsequent development of preeclampsia and pregnancy-induced hypertension in these women. The enzyme value was significantly higher in those who developed preeclampsia. Its sensitivity and specificity for the prediction of the disorder were 80% and 78% respectively. The positive predictive value was 21% while the negative predictive value was 98%.     

Scheduling techniques for reducing processor energy use in MacOS

The CPU is one of the major power consumers in a portable computer, and considerable power can be saved by turning off the CPU when it is not doing useful work. In Apple's MacOS, however, idle time is often converted to busy waiting, and generally it is very hard to tell when no useful computation is occurring. In this paper, we suggest several heuristic techniques for identifying this condition, and for temporarily putting the CPU in a low‐power state. These techniques include turning off the processor when all processes are blocked, turning off the processor when processes appear to be busy waiting, and extending real time process sleep periods. We use trace‐driven simulation, using processor run interval traces, to evaluate the potential energy savings and performance impact. We find that these techniques save considerable amounts of processor energy (as much as 66%), while having very little performance impact (less than 2% increase in run time). Implementing the proposed strategies should increase battery lifetime by approximately 20% relative to Apple's current CPU power management strategy, since the CPU and associated logic are responsible for about 32% of power use; similar techniques should be applicable to operating systems with similar behavior. This revised version was published online in June 2006 with corrections to the Cover Date.     

The disability index analysis system via an ergonomics, expert systems, and multiple attribute decision-making process

Through rehabilitation and training, visually impaired people can be placed in types of jobs that are compatible with their abilities. A functional assessment approach should be established to measure the physical ability of handicapped people in response to specific tasks and environmental demands. The objective of this study is to develop an integrated computerized system, entitled VITAL (Vision Impaired Task and Assignment Lexicon), to measure the vision impaired worker's residual capabilities and to provide the necessary recommendations for job accommodations. VITAL includes two major modules: the disability index, and the ergonomics consultation module. A single measure, the Disability Index (DI), which represents capacities of vision impaired individuals through a range of skill tests is developed via Multiple Attribute Decision Making (MADM) procedures. The resulting DI can be used in identifying the functional deficits and limitations of the visually impaired worker, and matching the visually impaired people to appropriate employment. This information is also used in the ergonomic consultation module to provide recommendations regarding job and workplace design for the vision impaired worker.     

The influence of process variations on the robustness of an audio power IC

In this paper the influence of process variations on the robustness of an audio power IC is discussed. The effect of the variations in breakdown voltages on the robustness is evaluated with SOAR measurements on the power transistors and loaddump tests.     

RVE-based multilevel method for periodic heterogeneous media with strong scale mixing

A Representative Volume Element based multilevel (multigrid) solution method for wave propagation problems in periodic heterogeneous media is developed. The intergrid transfer operators are constructed from the solution of the Representative Volume Element (RVE) problem. It is shown that the convergence of the RVE-based multilevel method improves with increasing material heterogeneity and decreasing time integration step. Numerical results confirm theoretical estimates.