I discuss recent HST observations and interpretation of low-z Lyα clouds toward nearby Seyferts and QSOs, including their frequency, space density, estimated mass, association with galaxies, and contribution to Ωb. Our HST/GHRS detections of 73 Lyα absorbers with NHI ≥ 10 12.6 cm along 11 sightlines covering pathlength ∆(cz) = 86, 000 km s show f(> NHI) ∝ N −0.6±0.2 HI . A group of strong absor...

Continuous-wave near-infrared spectroscopy and near-infrared imaging enable the measurement of relative concentration changes in oxy- and deoxyhemoglobin and thus hemodynamics and oxygenation. The accuracy of determined changes depends mainly on the modeling of the light transport through the probed tissue. Due to the highly scattering nature of tissue, the light path is longer than the source-...

In this paper we study networks that have been optimized to realize a trade-off between communication efficiency and dynamical resilience. While the first is related to the average shortest pathlength, we argue that the second can be measured by the largest eigenvalue of the adjacency matrix of the network. Best efficiency is realized in starlike configurations, while enhanced resilience is rel...

The development of a compact tunable mid-IR laser system at 3.5 micrometers for quantitative airborne spectroscopic trace gas absorption measurements is reported. The mid-IR laser system is based on difference frequency generation (DFG) in periodically poled LiNbO3 and utilizes optical fiber amplified near-IR diode and fiber lasers as pump sources operating at 1083 nm and 1562 nm, respectively....

If buffer/indicator systems are used as optical thermometers in multicuvettes, the temperature resolution is limited by errors of optical measurements produced mainly by variations of pathlength and blank transmittance of the wells. Theoretical and practical approaches show that, in multicuvettes, a between-well temperature resolution of < 0.05 degrees C can be achieved by multiwavelength photo...

proving to be a powerful separation technique. Electrochemical (EC) methods offer significant advantages over classical spectroscopic techniques for CE separations because electrochemistry occurs directly at an electrode surface and, thus, the limits of detection are not compromised by the small dimensions inherent in CE. This is in contrast to spectrophotometric detectors, in which the signal ...

The urban public transport network (UPTN) in Nanjing is characterized by a complex network with topological pedestals. The empirical data indicates that it is a small-world network. Under malicious attack to the high connectivity nodes of the network, the average pathlength will increase 2.5 times, the reliability and traffic capacity of the UPTN will greatly decline, and the travel expenditure...

We propose to maintain a Binary Search Tree in the form of a forest in such a way that – (a) it provides faster node access and, (b) it becomes more compatible with the concurrent environment. Using a small array, the stated goals were achieved without applying any restructuring algorithm. Empirically, we have shown that the proposed method brings down the total internal pathlength of a Binary ...

A trajectory generation strategy that facilitates the coordination of multiple unmanned air vehicles is developed. Of particular interest is the planning of threat-avoiding trajectories that result in the simultaneous arrival of multiple UAVs at their targets. In this approach, paths to the target are modeled using the physical analogy of a chain. A unique strength of the planning approach is t...

This paper presents a simple, rapid and effective method for ammonia determination in a flow analysis regime using Nessler's reagent. The proposed modification of the common flow procedure results in the total elimination of the problem of precipitate deposition inside the flow manifold. The improved procedure has been adapted to a flow analysis system based on microsolenoid pumps combined with...