Persistence of UK Real Estate returns: a Markov chain analysis

The persistence of investment performance is a topic of perennial interest to investors. Efficient Markets theory tells us that past performance can not be used to predict future performance yet investors appear to be influenced by the historical performance in making their investment allocation decisions. The problem has been of particular interest to investors in real estate; not least because reported returns from investment in real estate are serially correlated thus implying some persistence in investment performance. This paper applies the established approach of Markov Chain analysis to investigate the relationship between past and present performance of UK real estate over the period 1981 to 1996. The data are analysed by sector, region and size. Furthermore some variations in investment performance classification are reported and the results are shown to be robust

Correlations between deposition parameters and structural and electrical properties of YBa2Cu3O7–delta thin films grown in situ by sequential ion beam sputtering

We have studied the correlations between deposition parameters and structural and electrical properties of YBa2Cu3O7–delta thin films grown in situ by sequential ion beam sputtering. Epitaxial, c-axis oriented YBa2Cu3O7–delta films were grown both on (100) SrTiO3 and on (100) MgO substrates following the stacking sequence of the ``123'' compound, with deposited layer thicknesses nominally equal to 1 monolayer. The c-axis lattice parameters obtained were larger than the corresponding lattice parameter in bulk samples, even after low-temperature anneals in O2. The transition temperatures were found to decrease with the enlargement of the c-axis lattice parameter. A clear correlation between growth temperature and the value of the c-axis lattice parameter was observed. The c-axis lattice parameter and the x-ray linewidth of Bragg reflections with the G vector along the c-axis were also found to be correlated. This suggests a relationship between the c-axis lattice parameter and the structural coherence of the epitaxial films

Ferromagnetism below 10 K in Mn doped BiTe

Ferromagnetism is observed below 10 K in [Bi0.75Te0.125Mn0.125]Te. This material has the BiTe structure, which is made from the stacking of two Te-Bi-Te-Bi-Te blocks and one Bi-Bi block per unit cell. Crystal structure analysis shows that Mn is localized in the Bi2 blocks, and is accompanied by an equal amount of TeBi anti-site occupancy in the Bi2Te3 blocks. These TeBi anti-site defects greatly enhance the Mn solubility. This is demonstrated by comparison of the [Bi1-xMnx]Te and [Bi1-2xTexMnx]Te series; in the former, the solubility is limited to x = 0.067, while the latter has xmax = 0.125. The magnetism in [Bi1-xMnx]Te changes little with x, while that for [Bi1-2xTexMnx]Te shows a clear variation, leading to ferromagnetism for x > 0.067. Magnetic hysteresis and the anomalous Hall Effect are observed for the ferromagnetic samples.Comment: Accepted for publication in Phys. Rev.

SeaSat-A Satellite Scatterometer Mission Summary and Engineering Assessment Report

The SeaSat-A satellite was launched on June 26, 1978 and operated in orbit through October 9, 1978. The SeaSat-A satellite scatterometer ocean surface wind field sensor began taking data on July 10, 1978 with virtually continuous operation for 95-1/2 days. A review of mission events significant to the scatterometer and a report on the hardware and software engineering assessment are presented

Wind-tunnel tests of wide-chord teetering rotors with and without outboard flapping hinges

Wind tunnel tests of aeroelastically designed helicopter rotor models were conducted to obtain rotor aerodynamic performance and dynamic response data pertaining to two-bladed teetering rotors with a wider chord and lower hover tip speed than currently employed on production helicopters. The effects of a flapping hinge at 62 percent radius were also studied. Finally, the effects of changing tip mass on operating characteristics of the rotor with the outboard flapping hinge were examined. The models were tested at several shaft angles of attack for five advance ratios, 0.15, 0.25, 0.35, 0.40, and 0.45. For each combination of shaft angle and advance ratio, the rotor lift was varied over a wide range to include simulated maneuver conditions. At each test condition, rotor aerodynamic performance and dynamic response data were obtained. From these tests, it was found that wide-chord rotors may be subject to large control forces. An outboard flapping hinge may be used to reduce beamwise bending moments over a significant part of the blade radius without significantly affecting the chordwise bending moments

High-temperature, long-life polyimide seals for hydraulic actuator rods

Two types of polyimide seals are developed for hydraulic actuator rod in low pressure second stage of two-stage configuration. Each seal melts test objectives of twenty million cycles of operation at 534 K. Analytical and experimental study results are discussed. Potential applications are given

An underground cosmic ray muon telescope for observation of cosmic ray anisotropy

A telescope housed in a tunnel laboratory has an overburden of 573 hg cm(-2) and is located under the center of a saddle-shaped landscape. It is composed of triple layers of proportional counters, each layer of area approx. 4m x 2m and their separation 0.5m. Events are selected by triple coincidence and software track identification. The telescope is in operation for over a year and the overall count rate is 1280 hr(-1). The structure and operation of the system is reported

Computer programs for prediction of structural vibrations due to fluctuating pressure environments. Volume 1 - Theoretical analyses Final report

Theoretical analyses for computer program to calculate random vibrations of reinforced rectangular cylindrical panels in fluctuating pressure environmen

Cooling load forecasting-based predictive optimisation for chiller plants

Extensive electric power is required to maintain indoor thermal comfort using heating, ventilation and air conditioning (HVAC) systems, of which, water-cooled chiller plants consume more than 50% of the total electric power. To improve energy efficiency, supervisory optimisation control can be adopted. The controlled variables are usually optimised according to instant building cooling load and ambient wet bulb air temperature at regular time intervals. In this way, the energy efficiency of chiller plants has been improved. However, with an inherent assumption that the instant building cooling load and ambient wet bulb temperature remain constant in the coming time interval, the energy efficiency potential has not been fully realised, especially when cooling loads vary suddenly and extremely. To solve this problem, a cooling load forecasting-based predictive optimisation method is proposed. Instead of minimising the instant system power according to the instant building cooling load and ambient wet bulb temperature, the controlled variables are derived to minimise the sum of the instant system power and one-time-step-ahead future system power according to both instant and forecasted future building cooling loads. With this method, the energy efficiency potential of a chiller plant can be further improved without shortening the operation time interval. 80% redundant energy consumption has been reduced for the sample chiller plant; energy can be saved for chiller plants that work for years. The evaluation on the effect of cooling load forecasting accuracy turns out that the more accurate the forecasts are, the more redundant energy consumption can be reduced