How large is the spreading width of a superdeformed band?

Recent models of the decay out of superdeformed bands can broadly be divided into two categories. One approach is based on the similarity between the tunneling process involved in the decay and that involved in the fusion of heavy ions, and builds on the formalism of nuclear reaction theory. The other arises from an analogy between the superdeformed decay and transport between coupled quantum dots. These models suggest conflicting values for the spreading width of the decaying superdeformed states. In this paper, the decay of superdeformed bands in the five even-even nuclei in which the SD excitation energies have been determined experimentally is considered in the framework of both approaches, and the significance of the difference in the resulting spreading widths is considered. The results of the two models are also compared to tunneling widths estimated from previous barrier height predictions and a parabolic approximation to the barrier shape

The Behaviour of Two Trial Embankments at Perlis, Malaysia With Different Rates of Construction

Two trial embankments namely the North and South trial embankments were constructed in the state of Perlis, Peninsular Malaysia. The embankments have a finished height of 4m and dimensions of 60m in width and 90m in length and wen; constructed side by side. The trial embankments were staged constructed with a counterberm at 2m and side slopes of 2:3. The South trial embankment was rapidly constructed in 36 days while the North embankment was slowly constructed in about one year. Detailed site investigation works included borehole logging, field and laboratory testing. These were carried out to obtain the subsoil profile and geotechnical parameters of the subsoils at the trial site. Geotechnical instrumentation installed to monitor the behaviour of the embankments including settlement plates, heave markers, pneumatic piezometers and inclinometers. This paper briefly describes the location of the trial site, the detailed layout and the construction details of the embankments. Geotechnical parameters for the fill and the subsoil profile obtained from the detailed site investigation works are briefly described. The behaviours of the two embankments identified from various geotechnical instrumentation are described

Failure Investigation of a Fill Slope in Putrajaya, Malaysia

On 6th of January 2001, a fill slope collapsed in Putrajaya, Malaysia. The failed slope was 25m in height. The failure caused the slope to pushed two reinforced earth walls and the recently completed jetty and boat docking facilities to collapse. The depth of the failure scar was about 2m with a failure length of about 50m. A failure investigation was then carried out to determine the causes of failure. A total of thirteen new boreholes, fifteen Mackintosh probes and three hand augers were carried out to determine the soil profile. A desk study of existing information and records, site reconnaissance and mapping of the failure area was also carried out to determine the causes and the extent of the failure. Some of the findings of the failure investigation are there were no pile slab found at reinforced earth wall W2 as stated in the drawings and the groundwater table has risen as a result of the filling of the lake, which was carried out after the construction of the fill slope. The groundwater table at failure was found to be much higher than those measured during the site investigation works. Seepages of water were also seen from the failed area

Addendum: Attenuation of the intensity within a superdeformed band

We investigate a random matrix model [Phys. Rev. C {\bf 65} 024302 (2002] for the decay-out of a superdeformed band as a function of the parameters: $\Gamma^\downarrow/\Gamma_S$, $\Gamma_N/D$, $\Gamma_S/D$ and $\Delta/D$. Here $\Gamma^\downarrow$ is the spreading width for the mixing of an SD state $|0>$ with a normally deformed (ND) doorway state $|d>$, $\Gamma_S$ and $\Gamma_N$ are the electromagnetic widths of the the SD and ND states respectively, $D$ is the mean level spacing of the compound ND states and $\Delta$ is the energy difference between $|0>$ and $|d>$. The maximum possible effect of an order-chaos transition is inferred from analytical and numerical calculations of the decay intensity in the limiting cases for which the ND states obey Poisson and GOE statistics. Our results show that the sharp attenuation of the decay intensity cannot be explained solely by an order-chaos transition.Comment: 4 pages, 4 figures, submitted to Physical Review

Energy averages over regular and chaotic states in the decay out of superdeformed bands

We describe the decay out of a superdeformed band using the methods of reaction theory. Assuming that decay-out occurs due to equal coupling (on average) to a sea of equivalent chaotic normally deformed (ND) states, we calculate the average intraband decay intensity and show that it can be written as an ``optical'' background term plus a fluctuation term, in total analogy with average nuclear cross sections. We also calculate the variance in closed form. We investigate how these objects are modified when the decay to the ND states occurs via an ND doorway and the ND states' statistical properties are changed from chaotic to regular. We show that the average decay intensity depends on two dimensionless variables in the first case while in the second case, four variables enter the picture.Comment: 8 pages, 1 figure, presented at FUSION03, Matsushima, Miyagi, Japan, Nov 12-15, 2003, to appear in Progress of Theoretical Physics; corrected typo

Design and Implemetation of FPGA based Software Defined Radio Using Simulink HDL Coder

This paper presents the design procedure and implementation results of a proposed software defined radio (SDR) using Altera Cyclone II family board. The implementation uses Matlab/SimulinkTM, Embedded MatlabTM blocks, and Cyclone II development and educational board. The design has first implemented in Matlab/SimulinkTM environment. It is then converted to VHDL level using Simulink HDL coder. The design is synthesized and fitted with Quartus II 9.0 Web Edition® software, and downloaded to Altera Cyclone II board. The results show that it is easy to develop and understand the implementation of SDR using programmable logic tools. The paper also presents an efficient design flow of the procedure followed to obtain VHDL netlists that can be downloaded to FPGA boards