Energy management for battery-powered reconfigurable computing platforms

We define portable reconfigurable computing platforms as those which have some form of configurable logic coupled with other on-chip or off-chip processing units such as soft processors, embedded processors, and voltage-scalable processors. In the first part of this paper, we present and test a unique methodology where we dynamically change the active area of a field programmable gate array (FPGA) to vary the battery usage and lifetime of the system, by running it on several different taskgraph structures and report an average of 14% and as high as 21%, less battery capacity used, as compared to nonoptimal execution. In the second part of this paper, we integrate the above methodology with more traditional voltage and frequency scaling techniques for portable systems and present a heuristic iterative algorithm for single and multiple processing units. The iterative heuristic algorithm finds a sequence of tasks along with an appropriate design point (implementation option) for each task, such that a deadline is met and the amount of battery energy used is as small as possible. We have used several real-world benchmarks to test the effectiveness of this methodology and we will present the results.     

Capacitor coupled converter (C3) for high power DCconversion

The bang-bang controlled capacitor coupled converter (C³) is described in this paper. Due to the converter's inherent commutating property, the C³ can accommodate thyristors as well as high-power gate turn-off switches, due to zero-current switching transitions. The zero-current switching is achieved at no current stress increase, therefore, the topology is considered appropriate for high-power processing. DC and small signal AC models are derived for the bang-bang controlled C³, a design procedure is proposed, and simulation results are discussed. Finally, oscillograms from a proof of principle prototype circuit are presented     

Rheumatic heart disease in India

A cross-sectional study was carried out in rural areas of Jawan Block, District Aligarh, Uttar Pradesh, India, covering a total population of 3760 drawn from 11 villages. The total number of confirmed cases of rheumatic heart disease was 24 with a prevalence rate of 6.4 per 1000 of the general rural population. The prevalence of rheumatic heart disease increased with age until the age of 25 years. Females were more prone to rheumatic heart disease compared to males. Socio-economic class had a direct impact on the occurrence of rheumatic heart disease.     

The influence of chloride-ion concentration on the Pitting of steel in simulated concrete environment

The influence of chloride-ion concentration on the pitting behaviour of steel in saturated Ca(OH)₂ solution was studied using the D.C. polarization technique. Results seem to indicate a threshold chloride level for the on-set of severe pitting around 3000 ppm, the pitting potential E_p exhibits dramatic drop and large hysteresis loops develop. The results provide insight into the pitting performance of steel in concrete and highlight the poor repassivation of this metal/environment system.     

Prostate cancer clinical trials of the Southwest Oncology Group

The changing clinical dynamics of prostate cancer have resulted in a broadening of the research focus of the Genitourinary (GU) Cancer Committee of the Southwest Oncology Group (SWOG). Beginning with an emphasis on hormone-refractory disease in its early years, SWOG prostate cancer trials now cover the entire spectrum of the disease: localized, locally advanced, metastatic and hormone-refractory disease. As the world's largest GU cancer research group, the GU committee of SWOG has pioneered studies in combined androgen therapy for metastatic disease, quality-of-life (QOL) assessments for patients with localized and advanced disease, adjuvant therapy models, and prostate cancer chemoprevention. The committee has also formed the GU Global Group, whose purpose is to convene the chairs of the GU committees of all the major national and international oncology cooperative groups. Meeting semiannually, this group discusses activities within their respective organizations, plans collaborative strategies and protocols, and establishes global strategy in prostate cancer clinical research. The future directions of national and international prostate cancer trials will build on this broad foundation of well-conceived, logically sequenced studies.     

Principles of high-resolution radar based on nonsinusoidal waves.II. Generalized ambiguity function

For pt.I see ibid., vol.31, no.4, p.359-68 (1989). A generalized ambiguity function for nonsinusoidal coded waveforms that are represented as a train of properly weighted Gaussian pulses is derived and analyzed to study its properties. Computer plots of generalized ambiguity functions of different binary codes, e.g. Barker, complementary, and pseudorandom codes, are presented. The various computer plots show that the desired thumbtack ambiguity function is achievable by nonsinusoidal coded waveforms     

Diurnal and environmental characterization of solar photovoltaic panels using a PC-AT add on plug in card

This article describes the development of an instrumentation system for characterizing photovoltaic panels. It uses an add on card (which contains DAC, ADC and digital input/output ports) in conjunction with a PC-AT. The panels in a field are selected in succession through a set of relays actuated by the digital output port. The selected panel is loaded in discreet steps by a transistor loading circuit which is activated by the digital to analog convertor to trace the most significant portion of the I-V curve. The data shows that the power output is invariably lower than that specified by the manufacturer. The reasons for drop in output have been analyzed. It is shown that these effects can be represented by the curvature of I-V characteristic at the maximum power point (OP). The loss of power due to accumulation of dust and the increase in temperature of the panels can be significant.     

Differential cellular response within the rabbit tendon unit following tendon injury

Since 1975, 340 patients were treated by tracheal sleeve resection for tracheal or subglottic laryngeal iatrogenic stenoses in our unit. Preoperative iterative Nd YAG laser sessions have usually been performed, without success. The length of the sleeve specimen was an average of 3 1/4 cm. Twelve patients died on the post operative course (3.5%), 3 more patients died later after failure of the procedure (0.9%) and nineteen had recurrent stenoses treated with use of a tracheostomy tube, a permanent Montgomery tube, or an endotracheal stent (5.6%). Three hundred and six patients are definitely cured (90%), at the first attempt for 265 patients, after a laser session for granulomas for 20 patients, after a second tracheal resection for 6 patients and after a temporary Montgomery tube for 15 patients. Providing there is a good selection of the patients, tracheal sleeve resection is the best treatment for iatrogenic stenosis.