Optical demultiplexing at 6 Gb/s using a semiconductor laser amplifier as an optical gate

A semiconductor laser amplifier (SLA) has been employed successfully for optical demultiplexing in two-channel optical time division multiplexed system experiments at 6 and 2 Gb/s. Demultiplexing of 6-Gb/s (2-Gb/s) signals was demonstrated with a power penalty of 1.6 dB (3.0 dB) at bit error rates of 10/sup -9/. It is also shown that a reduction of the generated amplified spontaneous emission can be obtained by optical gating/demultiplexing for systems incorporating inline amplifiers. A 0.5-dB improvement in sensitivity was achieved as a result of using an SLA for demultiplexing from 2.0 to 1.0 Gb/s in a system with one inline Er/sup 3+/-doped fiber amplifier.<>     

High output power single longitudinal mode graded index separateconfinement multiple quantum well InGaAs/InP distributed feedback (GRINSCH MQW DFB) lasers

A high continuous-wave (CW) output and high quantum efficiency of 1.5 μm-wavelength InGaAs/InP graded-index separate-confinement multiple-quantum-well DFB lasers were demonstrated. A threshold current of 45 mA with a maximum output power close to 100 mW and a quantum efficiency of 0.33 mW/mA was obtained. Single-frequency light output with power as high as 16 dBm (40 mW) was launched into a single-mode fiber     

IR连接传感器使温度监控变简单

测量对地有几十伏电压的电路元件的温度是困难的.而且,随着电压的增加,此工作变得更困难.在高EMI环境中测量温度也是困难的.解决这些难题的一个良好方案是靠红外(IR)信号实现温度探头到读出测定位的连接.     

Child custody cases: A content analysis of evaluations in practice.

Guidelines for custody evaluations recommend multiple ways for assessing the parent-child relationship and outline appropriate means of assessing special issues such as domestic violence, child abuse, and substance use. However, little is known about the implementation of these guidelines in practice. This study examines 60% of custody evaluations in one circuit court over a 2-year period. Custody evaluations were examined for adherence to guidelines and for differences based on evaluator training. This analysis suggests much variety in techniques used and a lack of consistency between guidelines and clinical practice. The findings suggest a need for more standardized approaches to conducting custody evaluations as well as the assessment of domestic violence, child abuse, and substance abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Injury prediction in a side impact crash using human body model simulation

Background

Improved understanding of the occupant loading conditions in real world crashes is critical for injury prevention and new vehicle design. The purpose of this study was to develop a robust methodology to reconstruct injuries sustained in real world crashes using vehicle and human body finite element models.

Methods

A real world near-side impact crash was selected from the Crash Injury Research and Engineering Network (CIREN) database. An average sedan was struck at approximately the B-pillar with a 290 degree principal direction of force by a lightweight pickup truck, resulting in a maximum crush of 45 cm and a crash reconstruction derived Delta-V of 28 kph. The belted 73-year-old midsized female driver sustained severe thoracic injuries, serious brain injuries, moderate abdominal injuries, and no pelvic injury. Vehicle finite element models were selected to reconstruct the crash. The bullet vehicle parameters were heuristically optimized to match the crush profile of the simulated struck vehicle and the case vehicle. The Total Human Model for Safety (THUMS) midsized male finite element model of the human body was used to represent the case occupant and reconstruct her injuries using the head injury criterion (HIC), half deflection, thoracic trauma index (TTI), and pelvic force to predict injury risk. A variation study was conducted to evaluate the robustness of the injury predictions by varying the bullet vehicle parameters.

Results

The THUMS thoracic injury metrics resulted in a calculated risk exceeding 90% for AIS3+ injuries and 70% risk of AIS4+ injuries, consistent with her thoracic injury outcome. The THUMS model predicted seven rib fractures compared to the case occupant's 11 rib fractures, which are both AIS3 injuries. The pelvic injury risk for AIS2+ and AIS3+ injuries were 37% and 2.6%, respectively, consistent with the absence of pelvic injury. The THUMS injury prediction metrics were most sensitive to bullet vehicle location. The maximum 95% confidence interval width for the mean injury metrics was only 5% demonstrating high confidence in the THUMS injury prediction.

Conclusions

This study demonstrates a variation study methodology in which human body models can be reliably used to robustly predict injury probability consistent with real world crash injury outcome.     

Optimal gate sizing using a self-tuning multi-objective framework

In this paper, we present a self-tuning multi-objective framework for geometric programming that provides a fine trade-off between the competing objectives. The significance of this framework is that the designer does not need to perform any tuning of weights of objectives. The proposed framework is applied to gate sizing and clock network buffer sizing problems. In gate sizing application, power consumption is reduced on average by 86% while delay sees only an increase of 34 ns. In clock network butter sizing application, our framework results in a significant reduction in power, 57%, and an improvement of 31 ps in skew.     

Efficient recovery of nano-sized iron oxide particles from synthetic acid-mine drainage (AMD) water using fuel cell technologies

Acid mine drainage (AMD) is an important contributor to surface water pollution due to the release of acid and metals. Fe(II) in AMD reacts with dissolved oxygen to produce iron oxide precipitates, resulting in further acidification, discoloration of stream beds, and sludge deposits in receiving waters. It has recently been shown that new fuel cell technologies, based on microbial fuel cells, can be used to treat AMD and generate electricity. Here we show that this approach can also be used as a technique to generate spherical nano-particles of iron oxide that, upon drying, are transformed to goethite (α-FeOOH). This approach therefore provides a relatively straightforward way to generate a product that has commercial value. Particle diameters ranged from 120 to 700 nm, with sizes that could be controlled by varying the conditions in the fuel cell, especially current density (0.04-0.12 mA/cm²), pH (4-7.5), and initial Fe(II) concentration (50-1000 mg/L). The most efficient production of goethite and power occurred with pH = 6.3 and Fe(II) concentrations above 200 mg/L. These results show that fuel cell technologies can not only be used for simultaneous AMD treatment and power generation, but that they can generate useful products such as iron oxide particles having sizes appropriate for used as pigments and other applications.     

Correction to Schneider and Logan (2006).

Reports an error in "Hierarchical Control of Cognitive Processes: Switching Tasks in Sequences" by Darryl W. Schneider and Gordon D. Logan (Journal of Experimental Psychology: General, 2006[Nov], Vol 135[4], 623-640). Two task transitions were classified incorrectly in Table 7 (p. 634). The task transition at Serial Position 1 for sequence switches of the AABB sequence should be TR instead of TS. The task transition at Serial Position 1 for sequence switches of the ABBA sequence should be TS instead of TR. Two sections of text in the Results and Discussion section of Experiment 4 were affected by the misclassifications. The corrected text is provided for the Error rate analysis section (pp. 634-635) and the RT analysis section (p.635). These corrections do not alter any of the conclusions drawn from the original text. (The following abstract of the original article appeared in record 2006-20327-009.) Hierarchical control of cognitive processes was studied by examining the relationship between sequence- and task-level processing in the performance of explicit, memorized task sequences. In 4 experiments, switch costs in task-switching performance were perturbed by sequence initiation times that varied with sequence complexity, preparation time, and type of sequence transition (repetition or switch). Hierarchical control was inferred from these sequence initiation time effects and the recurrent finding of no switch cost at the first serial position across sequences, the point at which sequence-level processes are likely active in maintaining or instantiating a hierarchical control structure in working memory. These findings resonate with past research on motor programs and serial memory and provide new insights into the concepts of task set and control. (PsycINFO Database Record (c) 2010 APA, all rights reserved)