On trip planning queries in spatial databases

In this paper we discuss a new type of query in Spatial Databases, called Trip Planning Query (TPQ). Given a set of points P in space, where each point belongs to a category, and given two points s and e, TPQ asks for the best trip that starts at s, passes through exactly one point from each category, and ends at e. An example of a TPQ is when a user wants to visit a set of different places and at the same time minimize the total travelling cost, e.g. what is the shortest travelling plan for me to visit an automobile shop, a CVS pharmacy outlet, and a Best Buy shop along my trip from A to B? The trip planning query is an extension of the well-known TSP problem and therefore is NP-hard. The difficulty of this query lies in the existence of multiple choices for each category. In this paper, we first study fast approximation algorithms for the trip planning query in a metric space, assuming that the data set fits in main memory, and give the theory analysis of their approximation bounds. Then, the trip planning query is examined for data sets that do not fit in main memory and must be stored on disk. For the disk-resident data, we consider two cases. In one case, we assume that the points are located in Euclidean space and indexed with an Rtree. In the other case, we consider the problem of points that lie on the edges of a spatial network (e.g. road network) and the distance between two points is defined using the shortest distance over the network. Finally, we give an experimental evaluation of the proposed algorithms using synthetic data sets generated on real road networks

On trip planning queries in spatial databases

In this paper we discuss a new type of query in Spatial Databases, called Trip Planning Query (TPQ). Given a set of points P in space, where each point belongs to a category, and given two points s and e, TPQ asks for the best trip that starts at s, passes through exactly one point from each category, and ends at e. An example of a TPQ is when a user wants to visit a set of different places and at the same time minimize the total travelling cost, e.g. what is the shortest travelling plan for me to visit an automobile shop, a CVS pharmacy outlet, and a Best Buy shop along my trip from A to B? The trip planning query is an extension of the well-known TSP problem and therefore is NP-hard. The difficulty of this query lies in the existence of multiple choices for each category. In this paper, we first study fast approximation algorithms for the trip planning query in a metric space, assuming that the data set fits in main memory, and give the theory analysis of their approximation bounds. Then, the trip planning query is examined for data sets that do not fit in main memory and must be stored on disk. For the disk-resident data, we consider two cases. In one case, we assume that the points are located in Euclidean space and indexed with an Rtree. In the other case, we consider the problem of points that lie on the edges of a spatial network (e.g. road network) and the distance between two points is defined using the shortest distance over the network. Finally, we give an experimental evaluation of the proposed algorithms using synthetic data sets generated on real road networks

Tourists' Attitudes Towards Tea Tourism: A Case Study in Xinyang, China

Tea tourism as a new niche market has become more and more popular. Through a case study in Xinyang, China, this research explores tourists' attitudes and perceptions toward tea and tea tourism, identifies who the potential tea tourists are, and compares their attitudes with others. One hundred seventy-nine questionnaires were administered; one-way ANOVA and chi-square test were used based on their willingness of tea tourism. The results suggest that tea tourists and non-tea tourists have significant differences in terms of their attitudes toward tea drinking and their willingness of buying tea as souvenir. Tea tourists are mainly tea lovers driven by their high interest in tea and tea culture; they tend to be both males and females (yet females show a significant higher percentage than males), between ages 31-40, who have a positive attitude toward tea drinking, and who often drink tea. This research also provides some marketing suggestions for this niche market

Comparative analysis of environmental performance of an office building using BREEAM and GBL

With rapid economic growth and urban expansion in China, the Chinese building sector is now facing the huge challenge of balancing its energy demand and pollution. In order to minimize the environmental impact, the Ministry of Housing Urban-Rural Development (MOHURD) has set an ambitious energy reduction target requiring that 30% of all new constructions to be green by 2020. This paper presents comparative analysis of two environmental rating systems: the latest version of Chinese Green Building Label (GBL 2014) released by the MOHURD in order to promote the market transformation of green buildings and Building Research Establishment Environmental Assessment Method (BREEAM 2014), the widely recognised environmental assessment methodology in the global construction industry. To compare the two environment assessment standards, a public office building currently under construction in Fujian (China) has been used as a case-study to rate its environmental credentials using both BREEAM and GBL. Results have shown that although both standards use a similar methodology, they require different levels of input data and may result in different ratings for the same building

Adaptability, Personality, and Social Support: Examining Links with Psychological Wellbeing Among Chinese High School Students

The first year of boarding senior high school marks a period of great change for students. The extent to which students are able to adjust to successfully navigate this change (adaptability) likely has an impact on their psychological wellbeing. It has also been theorized that students’ personality traits and perceived social support may impact upon their adaptability and, directly and/or indirectly through adaptability, influence their psychological wellbeing. However, the literature examining independent and mediating effects of adaptability on psychological wellbeing is sparse particularly among students from non-Western cultures. In the present study, 102 grade-one high school students in China, were surveyed for their personality, perceived social support, adaptability, and psychological wellbeing (life satisfaction, mental well-being, and psychological distress). Findings showed that adaptability (along with neuroticism, extraversion, and social support) made a significant independent contribution to students’ psychological wellbeing. Further, adaptability was found to fully mediate the relationships between personality (conscientiousness and neuroticism) and psychological wellbeing, and to partially mediate the relationships between extraversion and psychological wellbeing, and social support and psychological wellbeing. These findings have important theoretical and practical implications for researchers and educators who are seeking to support students’ adjustment to boarding senior high school

Multiscale Computational Modeling of Multiphase Composites with Damage

A multiscale computational framework for multiphase composites considering damage is developed in this research. In micro-scale, micromechanics based homogenization methods are used to estimate effective elastic moduli of graded Ti_(2)AlC/Al composites (GCMeCs) considering existence of damage (micro-voids). Then, in macro-scale, these properties are implemented in finite element model by using user material subroutine (UMAT) in Abaqus for numerical analysis of plate. In meso-scale, detailed 3D RVEs are created based on the microstructure of composites. Effective thermal and elastic properties are obtained from the corresponding FE models of 3D RVEs and compared with experimental results and micromechanics based homogenization methods. Two constitutive models are used to model plastic-damage behavior of two IPCs regarding their different material properties of constituent phases: (1) Due to the ductile properties of constituent phases for stainless-steel/bronze IPCs, a widely used porous plasticity constitutive model, Gurson-Tvergaard-Needleman (GTN) model, is adopted to investigate elastoplastic-damage behavior of stainless-steel/bronze IPCs. (2) For porous Ti_(2)AlC, a continuum damage mechanics (CDM) based plastic-damage coupled constitutive model is used to study damage evolution in porous Ti_(2)AlC, which can take distinct tensile and compressive inelastic behaviors of Ti_(2)AlC into consideration. From the simulation results of FE models of 3D RVEs, it is found that: Porosity and interfacial layer with low effective thermal conductivity lowers the overall heat flux flowing through NiTi/Ti_(3)SiC_(2) IPC. The existence of thermal residual stress within stainless-steel/bronze IPCs leads to plastic deformation, especially in bronze phase, which further results in reduction of apparent moduli subjected to uniaxial tension. Nucleation of the new voids, which occurs at the second-phase particles by decohesion of the particle-matrix interface, has the main contribution to the overall damage. For porous Ti_(2)AlC with aligned ellipsoid-like pores, tensile stress plays a very important role in local damage of porous Ti_(2)AlC due to the relatively low tensile strength and brittle-like tensile behavior of dense Ti_(2)AlC. Different than typical porous ceramic, porous Ti_(2)AlC fails in a quasi-brittle manner even with 30-40 vol. % porosity. The transversely isotropic material system has higher compressive strength in transverse direction than that in longitudinal direction

Continuum- based computational models of biological living cell

All living creatures, despite their profound diversity, share a common architectural building block: the cell. Cells are the basic functional units of life, yet are themselves comprised of numerous components with distinct mechanical characteristics. It is well established that cells have the ability to sense and respond to externally applied forces. However, the detailed mechanism of mechanosensation is still not clearly understood, and is an active area of research involving experimental and theoretical works. Mathematical modeling of the mechanical stimulus correlating to different experimental stimulation procedures forms the first step to understanding the mechanosensation in cellular system. In this thesis, a continuum -based computational model of living cells that explicitly incorporate the material properties of various cellular components are developed. In the constitutive modeling of cell, the continuum standard linear solid viscoelastic model (SLS), its natural extension for large scale deformation standard Neo-Hookean solid viscoelastic model (SnHS) as well as polymer mechanics- based dynamic shear modulus model was introduced. Finite element simulations of three widely used experiments- atomic force microscopy (AFM), magnetic twisting cytometry (MTC) and micropipette aspiration in the quantification of cell properties were carried out to verify the developed constitutive model. From the results of AFM finite element simulation, it was observed that the force-deformation and strain-relaxation curves obtained fit the experimental results very well. The influences of cytoplasm shear modulus which varies due to the formation of stress fiber, and cortex shear modulus which alters with the actin filament concentration factors and load frequency were systematically studied. Similarly, in magnetic twisting cytometry (MTC) simulation, the role of cytoplasm material properties, constant/sinusoidal forcing rates and various frequencies on the overall mechanical response of a cell was obtained. Numerical results are validated against experiments results. Micropipette aspiration simulation was also carried out in which the typical creep deformation test was carried out to study the viscoelastic behavior of the cell. Based on the results from finite element simulation, the effect of pipette radius, effect of cortex shear modulus and effect of pressure rate have been derived for the interpretation of the mechanical parameters from the micropipette aspiration

Effects of residents' tourism development expectation and tourism impacts perception on their attitude towards tourism in natural tourist destination: A Comparative study between China's Jiuzhaigou and the UK's New Forest National Parks

Local residents' perception of tourism impacts in tourist destinations has been found to affect their attitude towards tourism; however, there have been relatively few studies on the influence of residents' tourism development expectation on their attitude towards tourism. With the utilization of SPSS16.0 software, this paper, taking China's Jiuzhaigou and the UK's New Forest National Parks as case study areas, makes a comparative study on the influence of local residents' tourism development expectation and touirism impacts perception on their attitude towards tourism. And potentially possible reasons for the influence and the differences between these two cases have been conducted with a qualitative analysis. Some conclusions can be obtained as follows. (1) Local residents' tourism impacts perception, especially tourism benefit perception, directly influences their support of tourism development. (2) Tourism development expectation of local residents directly influences their tourism impacts perception, espetially their tourism benefit perception, and indirectly influences their attitude towards tourism development in the parks via the medium of tourism benefit perception. (3) Residents in both destinations hold positive tourism development expectation with minor differences between the two cases due to cultural differences. Tourism benefit perception of local residents in the two national parks is less and worse than their tourism development expectation, indicating that there is a great gap between their tourism development expectation and tourism impacts perception in these two case study areas. But the majority of local residents in these two parks still hold no negative attitude towards local tourism development in spite of the existing gap

Dipotassium samarium(III) molybdate(VI) phosphate(V), K2Sm(MoO4)(PO4)

The title compound, K2Sm(MoO4)(PO4), has been prepared under atmospheric conditions using a high temperature solution growth (HTSG) method. The structure of K2Sm(MoO4)(PO4) is isotypic with other A 2 M(MoO4)(PO4) compounds, where A = Na or K, and M = trivalent rare earth cation. It can be described as being built up from two-dimensional anionic layers with composition [Sm(MoO4)(PO4)]2− that are stacked along the c axis and are inter­connected by K+ cations which are in an eightfold coordination by O atoms. The SmO8, MoO4 and PO4 polyhedra exhibit 2 symmetry