Carbon dioxide dynamics of combined crops of wheat,cowpea, pinto beans in the Laboratory Biosphere closed ecological system

A mixed crop consisting of cowpeas, pinto beans and Apogee ultra-dwarf wheat was grown in the Laboratory Biosphere, a 40 m³ closed life system equipped with 12,000 W of high pressure sodium lamps over planting beds with 5.37 m² of soil. Similar to earlier reported experiments, the concentration of carbon dioxide initially increased to 7860 ppm at 10 days after planting due to soil respiration plus CO₂ contributed from researchers breathing while in the chamber for brief periods before plant growth became substantial. Carbon dioxide concentrations then fell rapidly as plant growth increased up to 29 days after planting and subsequently was maintained mostly in the range of about 200–3000 ppm (with a few excursions) by CO₂ injections to feed plant growth. Numerous analyses of rate of change of CO₂ concentration at many different concentrations and at many different days after planting reveal a strong dependence of fixation rates on CO₂ concentration. In the middle period of growth (days 31–61), fixation rates doubled for CO₂ at 450 ppm compared to 270 ppm, doubled again at 1000 ppm and increased a further 50% at 2000 ppm. High productivity from these crops and the increase of fixation rates with elevated CO₂ concentration supports the concept that enhanced CO₂ can be a useful strategy for remote life support systems. The data suggests avenues of investigation to understand the response of plant communities to increasing CO₂ concentrations in the Earth’s atmosphere. Carbon balance accounting and evapotranspiration rates are included.     

兰桂坊的“红磨坊”

到过法国的旅游者,一般都知道巴黎有两个著名的歌舞表演厅,—个是位于市中心香榭丽舍大道的丽都,一个是位于城北蒙马特高地脚下白色广场附近的红磨坊。屋顶上装着长长的、闪烁着红光的大叶轮的红磨坊则是较为地道的法国式歌舞厅。MCG公司以法国红磨坊红磨坊为设计理念,把次情景带进了香港兰桂坊酒店Bisous酒吧。然而Bisous的设计并非照搬红色的浪漫风情,而是将未来趋势的一种极简概念设计结合了新的元素,将红磨坊的主题得以抽象化和现代化。以现今最时新的手法,完整地呈现了红磨坊的内心世界,概念可能不算创新,但精彩程度符合了当下时尚的思想!     

Mismatched Filtering of Sonar Signals

A replica correlator (matched filter) is an optimum processor for a receiver employing a pulse of continuous wave (CW) signal in a white Gaussian noise background. In an active sonar, however, when the target of interest has low Doppler shift and is embedded in a high reverberation background, this is not so. High sidelobes of the correlator frequency response pass a significant portion of the signal contained in the mainlobe of the reverberation spectrum. In order to reduce the sidelobes of the correlator output spectrum and at the same time keep the increase in its 3 dB bandwidth to a small amount, we propose lengthening of the replica of the transmitted signal and weighting it by a Kaiser window. It is demonstrated that by extending the weighted replica by 50 percent compared with the transmitted signal, it is possible to reduce the sidelobe levels to at least 40 dB below the mainlobe peak, with the concomitant increase of the 3 dB band-width by less than 5 percent. The degradation in signal-to-noise ratio (SNR) performance for such a ?mismatched? filter receiver with respect to the matched filter is less than 1.5 dB.     

Stellar flares

Radio and X-ray observations of stellar flares provide the most direct probes of energy relaase particle acceleration, and energy transport on stars other than the Sun. In this review, the observational basis for our understanding of the flare phenomenon on other stars is briefly described and outstanding interpretive and theoretical issues are discussed. I shall confine my attention to objects which are solar-like, to the extent that they possess deep convective envelopes and display activity which is presumed to be magnetic in origin. These include pre-main sequence objects, classical flare stars, and close binaries. Future directions are briefly discussed.     

MMAE-Based Control with Space-Time Point Process Observations

A multiple model adaptive estimator (MMAE) has been formulated to estimate the state of a dynamic system modeled by a linear stochastic differential equation, from which measurements, described as a noise-corrupted space-time point process functionally related to that state, are extracted. Assumed certainty equivalence is used to combine such an estimator with the LQ full-state feedback controller to synthesize a practical, implementable controller. Performance of the estimator and resultant controller characteristics are investigated via simulation as a function of approximation method used to limit the full-scale estimator to finite dimensionality and also as a function of important parameters defining the dynamics and observation processes.     

Geometric aspects of long-term noncoherent integration

Long-term integration is defined as integration, perhaps interrupted, over time periods long enough for targets to move through volumes in space resolvable by the radar. Because the motion of the target is unknown prior to detection, long-term integration must be performed along multiple paths representing plausible target paths. The geometry of such a set of integration paths affects detection performance in several ways. The simplest implementation of long-term integration, using constant radial velocity paths, is investigated. The effects of path geometry on detection is quantified and optimized for a target whose motion is nearly radial but otherwise unknown     

Onboard system for measuring the parameters of wind vector during parking,starting and takeoff-landing modes for helicopter with aerometric and ion-beacon measuring channels

The problem and features of measuring the speed and the direction angle of the wind vector relative to the longitudinal helicopter axis during parking, starting and takeoff-landing modes by onboard means are considered. The construction principles, information processing algorithms and advantages of onboard system for measuring the wind vector parameters based on ion-beacon and aerometric measuring channels, are disclosed.