CityU Institutional Repository
http://dspace.cityu.edu.hk:80
The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material.2014-10-31T00:15:43ZS.P.A.C.E
http://dspace.cityu.edu.hk:80/handle/2031/174
Title: S.P.A.C.E
Authors: Lai, Alice Yee Man (賴綺雯)2003-03-01T00:00:00ZHedonic pricing in property sales and property rent
http://dspace.cityu.edu.hk:80/handle/2031/337
Title: Hedonic pricing in property sales and property rent
Authors: Chan, Tsz Kin (陳子健); Cheng, Chung Hon (鄭忠漢)
Abstract: This study applies the hedonic pricing model to Property Sales and Property Rent and the aim is to investigate whether the Property Sales and Property Rent are affected by different factors.
Two log forms of hedonic pricing models, with the same set of independent variables, are applied to Property Sales and Property Rent. The quantitative variables in our dataset are “Gross Area” and “Building Age” of a property and the dummy variables are defined to represent different qualitative attributes of the property in order to test if the attributes are considered as significant factors of Sales and Rent.
In conclusion, the positive common factors are “Gross Area”, “Sea View” and “MTR/KCR”. The three negative common factors are “Building Age”, “No. of Flats in the Building” and “No. of Bus/Minibus Routes”. On the other hand, the positive specific factor, for Sales is “High Level of Floor”, while the two positive specific factors for Rent are “South Direction” and “No. of Band 1 Schools” in the district of the property.2004-01-01T00:00:00ZAnalytical and numerical studies on local and nonlocal elastic bars in tension and neutralizer-based iterative methods
http://dspace.cityu.edu.hk:80/handle/2031/7427
Title: Analytical and numerical studies on local and nonlocal elastic bars in tension and neutralizer-based iterative methods
Authors: Zhu, Xiaowu (朱小武)
Abstract: In this thesis, we study some problems associated with both local and nonlocal elasticity
and, present the so-called neutralizer-based iterative methods for integral equations
of the second kind. The details are as follows.
The local problem is on the strain softening of materials. Strain-softening, i.e.,
the decrease of stress with the increase of strain, which is a common post-peak phenomenon that has been recorded for a variety of materials. Snap-back due to strain
softening may be one of the most interesting and the most common structural instability
phenomena observed in experiments. There have been many efforts in the past
decades to investigate strain-softening with localization experimentally, numerically,
and analytically. However, there is not any analytical study with general nonlinear
constitutive relations in the open literature which explores the role played by the convexity of the constitutive curve of the softening part and the coupling effect between
this convexity and the size. Also, both snap-back and snap-through were observed in
some experiments, but no analytical results are available for explaining the transition
from snap-back to snap-through.
Nonlocal elasticity is a growing direction of continuum mechanics nowadays.
There are many works contributed to this area. Due to the essential difficulty of the
integral equation, analytical approximate solutions are usually prohibited. Thus, many
existing literature devote to apply the approximate differential models suggested by
Eringen et al. However, one weak point of the approximations is that the possible boundary effects, which are present in the integral formulations, are neglected. Thus,
it would be desirable to have proper differential formulations which take into account
such effects. For this purpose, a first step is to know both qualitative and quantitative
behavior near the ends (e.g., the influences of the parameters). Thus, some analytical
solutions are needed to provide convincing results.
In this thesis, firstly for the local problem, we modify an existing model and set up
the stress-strain equations for the structure in the post-peak region, which are nonlinear
as compared with the bilinear case in the literature. After some analysis, we derive the
mathematical conditions for the occurrence of several important curves as frequently
observed in experiments, including the snap-through (which cannot be captured by the
bilinear assumptions). Two examples are also given to illustrate these cases, and the
post-peak curves are consistent with our theoretical predictions.
Secondly, for a static tension problem in nonlocal elasticity (the uniform case), we
apply an existing iterative method that are efficient for a special kind of kernel to handle
the resultant integral equation. By explicitly evaluating the integral in the second
iterative solution, we are able to get a good approximate analytical solution for this
problem. Some features of the nonlocal theory can then be closely examined, especially
the boundary effects. It seems that the analytical results obtained here would
give some insights into nonlocal theory, particularly for its applications in nanomaterials.
Moreover, in view of the boundary effects, we also present a new model for
nonuniform nonlocal bar-a varying volume fraction in the nonlocal phase. The numerical
results of different shapes of materials show that, as compared with a uniform
bar and that in local elasticity, the model herein shows more features, such as stress
concentration.
Thirdly, we present neutralizer-based iterative methods for integral equations of
the second kind. As is known to all, there is an abundant of numerical techniques
for solving integral equations, such as Neumann series, multi-grid method, GMRES and so on. Here, we introduce the concept of neutralizer, which is sometimes used
in dealing with integrals (e.g., the asymptotic expansions of integrals), to obtain the
neutralizer-based iterative method. Some features of such iterative method is numerically
explored. Several meaningful examples are given, showing that the methods
perform well as compared with some related methods.
Notes: CityU Call Number: QA931 .Z45 2012; vi, 102 leaves : ill. 30 cm.; Thesis (Ph.D.)--City University of Hong Kong, 2012.; Includes bibliographical references (leaves [95]-102)2012-01-01T00:00:00ZTheoretical investigation and numerical computation on meshless collocation method for solving partial differential equations
http://dspace.cityu.edu.hk:80/handle/2031/7426
Title: Theoretical investigation and numerical computation on meshless collocation method for solving partial differential equations
Authors: Zheng, Yanjun (鄭豔君)
Abstract: In the last decades, the use of radial basis functions (RBFs) has proven to be efficient
and robust in multivariate interpolation and solving partial differential equations
(PDEs). In this thesis we focus on the stability analysis using meshless collocation
method by RBFs for solving partial differential equations. The original umsymmetric
meshless collocation method was firstly introduced by E. Kansa in 1986. Hon and his
collaborators later extended the method to solve various nonlinear initial and boundary
value problems. In the first part of the thesis, we investigate the stability and convergence
of unsymmetric meshless collocation methods. Some theoretical results are
obtained based on the work of R. Schaback who gave a general framework for obtaining
error bounds and convergence of a large class of unsymmetric meshless numerical
methods in solving well-posed linear operator equations. For simplicity, we consider
in this thesis the standard Poisson boundary value problem (PBVP). Using the works
of F. J. Ward, H. Wendland and R. Arcangeli et al., we give in this thesis a stability
condition of meshless collocation methods in solving the PBVP. Based on the theoretical
stability result, in the second part of the thesis, we devise a meshless computational
algorithm for solving a real application problem arisen from financial option pricing
model. This involves the numerical techniques for solving a partial integro-differential
governing equation under some initial and boundary condition problem with unknown
free boundary. Numerical examples are given to verify the effectiveness, accuracy, and
robustness of the meshless collocation method.
Notes: CityU Call Number: QA377 .Z4427 2010; iv, 93 leaves : ill. 30 cm.; Thesis (Ph.D.)--City University of Hong Kong, 2010.; Includes bibliographical references (leaves 61-68)2010-01-01T00:00:00Z