A 40-43-Gb/s clock and data recovery IC with integrated SFI-5 1:16 demultiplexer in SiGe technology

A fully integrated OC-768 clock and data recovery IC with SFI-5 1:16 demultiplexer is designed in a 120-GHz/100-GHz (f/sub T//f/sub MAX/) SiGe technology. The 16 2.5-Gb/s outputs and additional deskew channel are compliant with the Serdes Framer Implementation Agreement Level 5 specification. The measured bit-error rate is <10/sup -15/. The measured jitter tolerance exceeds the mask specified in G.8251. The IC operates with 1.8-V and -5.2-V supplies and dissipates 7.5 W.     

Prediction of influence parameters on the hot rolling process using finite element method and neural network

In the present investigation, a hot rolling process of AA5083 aluminum alloy is simulated using the finite element method. The temperature distribution in the roll and the slab, the stress, strain and strain rate fields, are extracted throughout a steady-state analysis of the process. The main hypotheses adopted in the formulation are: the thermo-viscoplastic behavior of the material expressed by Perzyna constitutive equation and rolling under plane-deformation conditions. The main variables that characterize the rolling process, such as the geometry of the slab, load, rolling speed, percentage of thickness reduction, initial thickness of the slab and friction coefficient, have been expressed in a parametric form giving a good flexibility to the model. The convergence of the results has been evaluated using experimental and theoretical data available in the literature. Since the FE simulation of the process is a time-consuming procedure, an artificial neural network (ANN) has been designed based on the back propagation method. The outputs of the FE simulation of the problem are used for training the network and then, the network is employed for prediction of the behavior of the slab during the hot rolling process.     

Integrated niobium DC SQUID gradiometers for non-destructive evaluation and biomagnetism

We describe the design and fabrication of thin-film Nb gradiometers with integrated DC SQUIDs for use in non-destructive evaluation (NDE) and biomagnetism. Issues of sensitivity, imbalance and field response are considered. Results are presented from eddy-current NDE in an unshielded environment of aluminium plates with sub-surface flaws, and from biomagnetic measurements of spinal and peripheral nerve evoked fields.     

College students' time management: Correlations with academic performance and stress.

Many college students may find the academic experience very stressful (K. J. Swick, 1987). One potential coping strategy frequently offered by university counseling services is time management. 165 students completed a questionnaire assessing their time management behaviors and attitudes, stress, and self-perceptions of performance and grade point average (GPA). The study revealed 2 major findings. The Time Management Behavior Scale consists of 4 relatively independent factors; the most predictive was Perceived Control of Time. Students who perceived control of their time reported significantly greater evaluations of their performance, greater work and life satisfaction, less role ambiguity, less role overload, and fewer job-induced and somatic tensions. Findings are consistent with theory and advice on time management (e.g., R. S. Schuler; 1979) but also indicate that the dynamics of time management are more complex than previously believed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Network model for strip-fed cavity-backed printed slot antenna

An equivalent network for the strip-fed cavity-backed slot antenna is derived. The model is based on some physical insight into the problem. The various parameters of the network are derived from the experimental data on the input reflection parameter of the antenna. This model gives an insight into the strip-slot-cavity coupling and hence the working of the structure. It is also useful for predicting the performance of such practical antennas.     

Adsorption of cobalt by lignite

Studies similar to earlier ones which had established the feasibility of extracting nickel by the lignite adsorption route were conducted on the adsorption extraction of cobalt on lignite, and with equal success.Optimal values of variables such as pH, sorbent/sorbate ratio, adsorbent particle size, contact time, temperature, and the effect of excess ammonium carbonate were evaluated.The rate of adsorption of cobalt was found to be slower than that for nickel. However, the recovery of over 99% cobalt from ammoniacal carbonate solutions, at optimal conditions, was comparable to that for nickel.The cobalt was recoverable as metal, by ignition of the loaded lignite, or in solution, by elution with sulfuric acid in single or multiple stages.     

Nutritional and healthful aspects of cultured and culture-containing dairy foods

Nutritional and therapeutic qualities of fermented dairy products are reviewed. Partial hydrolysis of milk constituents (proteins, fats, and lactose) in yogurt, cheese, and other cultured dary foods appears to contribute to their increased digestibility. Lactase and other constituent enzymes of various culturing organisms should contribute to assimilation of lactose by lactose intolerant individuals. Several lactic cultures synthesize certain B-vitamins in fermented dairy products. In contrast, directly acidified dairy products do not exhibit such enhancement in B-vitamins. The hypocholestremic effect of milk is enhanced by fermentation or inclusion of lactic cultures. Lactobacillus acidophilus, Lactobacillus bulgaricus and other lactic organisms produce antimicrobial agents and natural antibiotics. However, production of natural antibacterial substances by different strains of the same species vary widely. These metabolites in cultured dairy products may be responsible for increased shelf life of the foods by inhibiting a wide spectrum of food spoilage organisms. Also, consumption of cultured products containing such natural antibacterial substances may provide the consumer with protection against disease organisms. Unfermented milk containing a specific culture or strain may be consumed to invest organisms for projected beneficial effects.