Some Prototype Examples for Expert Systems v.1

This report consists of the nineteen term project reports for the graduate-level course EE695G ” Expert Systems and Knowledge Engineering”, which was offered for the fall semester of 1984 in the School of Electrical Engineering. The purpose of the term project is to provide each student an opportunity of designing and implementing a prototype expert system. The application area of each of these expert systems was selected by the student(s) working on the projects. This report is published for the purpose of documenting these results for future reference by the students of the above-mentioned course and, possibly, other workers in expert systems. The nineteen reports are grouped into seven parts based on their application domains. Part 1 - Manufacturing consists of six reports, and Part II - Robotics contains three. Two reports in each of Part III - Vision and Part IV - Management, and one in each of Part V - Structural Engineering and Part VI - Automatic Programming. The last part, Part VII - Others, consists of four reports with different applications

Some Prototype Examples for Expert Systems v.2

This report consists of the nineteen term project reports for the graduate-level course EE695G ” Expert Systems and Knowledge Engineering”, which was offered for the fall semester of 1984 in the School of Electrical Engineering. The purpose of the term project is to provide each student an opportunity of designing and implementing a prototype expert system. The application area of each of these expert systems was selected by the student(s) working on the projects. This report is published for the purpose of documenting these results for future reference by the students of the above-mentioned course and, possibly, other workers in expert systems. The nineteen reports are grouped into seven parts based on their application domains. Part 1 - Manufacturing consists of six reports, and Part II - Robotics contains three. Two reports in each of Part III - Vision and Part IV - Management, and one in each of Part V - Structural Engineering and Part VI - Automatic Programming. The last part, Part VII - Others, consists of four reports with different applications

Experimental and Numerical Investigation on Progressive Collapse Resistance of Post-tensioned Precast Concrete Beam-Column Sub-assemblages

In this paper, four 1/2 scaled precast concrete (PC) beam-column sub-assemblages with high performance connection were tested under push-down loading procedure to study the load resisting mechanism of PC frames subjected to different column removal scenarios. The parameters investigated include the location of column removal and effective prestress in tendons. The test results indicated that the failure modes of unbonded post-tensioned precast concrete (PTPC) frames were different from that of reinforced concrete (RC) frames: no cracks formed in the beams and wide opening formed near the beam to column interfaces. For specimens without overhanging beams, the failure of side column was eccentric compression failure. Moreover, the load resisting mechanisms in PC frames were significantly different from that of RC frames: the compressive arch action (CAA) developed in concrete during column removal was mainly due to actively applied pre-compressive stress in the concrete; CAA will not vanish when severe crush in concrete occurred. Thus, it may provide negative contribution for load resistance when the displacement exceeds one-beam depth; the tensile force developed in the tendons could provide catenary action from the beginning of the test. Moreover, to deeper understand the behavior of tested specimens, numerical analyses were carried out. The effects of concrete strength, axial compression ratio at side columns, and loading approaches on the behavior of the sub-assemblages were also investigated based on validated numerical analysis

A Generalized Preferential Attachment Model for Business Firms Growth Rates: II. Mathematical Treatment

We present a preferential attachment growth model to obtain the distribution $P(K)$ of number of units $K$ in the classes which may represent business firms or other socio-economic entities. We found that $P(K)$ is described in its central part by a power law with an exponent $\phi=2+b/(1-b)$ which depends on the probability of entry of new classes, $b$. In a particular problem of city population this distribution is equivalent to the well known Zipf law. In the absence of the new classes entry, the distribution $P(K)$ is exponential. Using analytical form of $P(K)$ and assuming proportional growth for units, we derive $P(g)$, the distribution of business firm growth rates. The model predicts that $P(g)$ has a Laplacian cusp in the central part and asymptotic power-law tails with an exponent $\zeta=3$. We test the analytical expressions derived using heuristic arguments by simulations. The model might also explain the size-variance relationship of the firm growth rates.Comment: 19 pages 6 figures Applications of Physics in Financial Analysis, APFA

Observation of Zeeman effect in topological surface state with distinct material dependence

The helical Dirac fermions on the surface of topological insulators host novel relativistic quantum phenomena in solids. Manipulating spins of topological surface state (TSS) represents an essential step towards exploring the theoretically predicted exotic states related to time reversal symmetry (TRS) breaking via magnetism or magnetic field. Understanding Zeeman effect of TSS and determining its g-factor are pivotal for such manipulations in the latter form of TRS breaking. Here, we report those direct experimental observations in Bi2Se3 and Sb2Te2Se by spectroscopic imaging scanning tunneling microscopy. The Zeeman shifting of zero mode Landau level is identified unambiguously by judiciously excluding the extrinsic influences associated with the non-linearity in the TSS band dispersion and the spatially varying potential. The g-factors of TSS in Bi2Se3 and Sb2Te2Se are determined to be 18 and -6, respectively. This remarkable material dependence opens a new route to control the spins in the TSS.Comment: main text: 17 pages, 4 figures; supplementary: 15 pages, 7 figure

Automatic Construction of CSG Representation from Orthographic Projections

An algorithm has been designed to construct the CSG model of object from its 2D orthographic projections. The method proposed uses a top-down approach in which the existence of some 3D primitive (e.g. CUBE) is assumed and then different views are searched for appropriate elements to prove the assumption .The algorithm is applied to some examples and the results are demonstrated. A second algorithm has also been designed to implement the automatic input of line drawings. The drawings are first digitized using a high resolution scanner. After some preprocessing, the algorithm is applied to the image in order .to extract the relevant graphical elements, such as arcs and circles. Two examples are also demonstrated

On the use of colour reflectivity plots to monitor the structure of the troposphere and stratosphere

The radar reflectivity, defined as the range squared corrected power of VHF radar echoes, can be used to monitor and study the temporal development of inversion layer, frontal boundaries and convective turbulence. From typical featurs of upward or downward motion of reflectivity structures, the advection/convection of cold and warm air can be predicted. High resolution color plots appear to be useful to trace and to study the life history of these structures, particularly their persistency, descent and ascent. These displays allow an immediate determination of the tropopause height as well as the determination of the tropopause structure. The life history of warm fronts, cold fronts, and occlusions can be traced, and these reflectivity plots allow detection of even very weak events which cannot be seen in the traditional meteorological data sets. The life history of convective turbulence, particular evolving from the planetary boundary layer, can be tracked quite easily. Its development into strong convection reaching the middle troposphere can be followed and predicted

The first operation and results of the Chung-Li VHF radar

The Chung-Li Very High Frequency (VHF) radar is used in the dual-mode operations, applying Doppler beam-swinging as well as the spaced-antenna-drift method. The design of the VHF radar is examined. Results of performance tests are discussed

Analysis and Design of Digital Control Systems

All digital control systems contain at least one signal which is sampled in time and quantized in amplitude. Design of these systems is often based on the assumption that a very large number of levels of quantization is available leading to the approximation of the basically nonlinear system by a linear one. If the actual system is constructed so that the linear assumption is satisfied, the performance may be excellent but other design factors such as reliability, cost, weight, and power consumption may be very unsatisfactory. On the other hand, if the actual system is constructed so that only a few levels of quantization are available, the other factors may be quite satisfactory but a previously well-behaved system may now possess limit cycle oscillations, large static errors, and an objectionable transient response. Thus, an important problem in the field of digital control is the development of analysis and design procedures such that the designer has the freedom to select quantization schemes not satisfying the linear approximation but producing an overall satisfactory design. Two techniques are presented as a partial solution to the above problem. The first is based on a study of certain properties unique to quantized sampled-data system and uses Laplace transforms to carry out the analysis. It leads to closed form solutions but appears to be somewhat restricted in the class of systems to which it can be applied. The second technique is a numerical procedure based on the state transition method and uses a digital computer to carry out the numerical calculations, It is not limited by input type, order of the plant, state variables having other than zero initial conditions, or quantizer complexity. Using the first method, some closed form solutions are obtained for first and second order systems and the results favorably compared with the results obtained by the more general second method. Where possible the results of the second method are compared with the results of other workers. In other cases, typical results are checked by comparison with results from simulation on an analog computer. In all cases favorable comparisons are obtained. Design charts prepared by the numerical procedure are presented and examples given demonstrating their use to satisfy specifications on static accuracy, response time, and presence or absence of either overshoot or limit cycle oscillations. A set of rules are derived describing certain properties of the system^ e.g. a final value rule similar to the final value theorem for linear systems is obtained. These rules are found to he useful in , both analysis and design by reducing the number of computations required to solve a given problem, by providing physical insight into system operation, and by furnishing a check on certain result

Entanglement and Quantum Phases in the Anisotropic Ferromagnetic Heisenberg Chain in the Presence of Domain Walls

We discuss entanglement in the spin-1/2 anisotropic ferromagnetic Heisenberg chain in the presence of a boundary magnetic field generating domain walls. By increasing the magnetic field, the model undergoes a first-order quantum phase transition from a ferromagnetic to a kink-type phase, which is associated to a jump in the content of entanglement available in the system. Above the critical point, pairwise entanglement is shown to be non-vanishing and independent of the boundary magnetic field for large chains. Based on this result, we provide an analytical expression for the entanglement between arbitrary spins. Moreover the effects of the quantum domains on the gapless region and for antiferromagnetic anisotropy are numerically analysed. Finally multiparticle entanglement properties are considered, from which we establish a characterization of the critical anisotropy separating the gapless regime from the kink-type phase.Comment: v3: 7 pages, including 4 figures and 1 table. Published version. v2: One section (V) added and references update