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1.Relational Power: An Extension and Analysis of Leader Power Types

Author:ZHAO Xinyu;SHANG Yufan;XI Youmin;LI Haiyun

Source:Science of Science and Management of S.&.T.(Monthly),2015,Vol.36

Abstract:Firstly, through reviewing and comparing the classic power models from the aspects of power type func-tion basis, obedience motivation and etc., this study noted that we should pay more attention to the relational power in organization context. Secondly, this study summarized the effects of personal relationship in the field of power research, suggesting that it is necessary to introduce and integrate the personal relationship research at the concep-tion-exploring period of relational power. Finally, this study attempts to answer questions such as: The definition, type division, function motivation and differences from classic power types of relational power.

2.2,2-Dicyanovinyl-end-capped oligothiophenes as electron acceptor in solution processed bulk-heterojunction organic solar cells

Author:Wu, J;Ma, Y;Wu, N;Lin, Y;Lin, J;Wang, L;Ma, CQ


Abstract:Three 2,2-dicyanovinyl (DCV) end-capped A-pi-D-pi-A type oligothiophenes (DCV-OTs) containing dithieno[3,2-b: 2',3'-d] silole (DTSi), cyclopenta[1,2-b: 3,4-b'] dithiophene (DTCP) or dithieno[3,2-b: 2',3'-d] pyrrole (DTPy) unit as the central donor part, mono-thiophene as the pi-conjugation bridge were synthesized. The absorption spectroscopies, cyclic voltammetry of these compounds were characterized. Results showed that all these compounds have intensive absorption band over 500-680 nm with a LUMO energy level around -3.80 eV, which is slightly higher than that of [6,6] phenyl-C-61-butyric acid methyl ester (PC61BM, E-LUMO = -4.01 eV), but lower than that of poly(3-hexylthiophene) (P3HT, ELUMO = -2.91 eV). Solution processed bulk heterojunction "all-thiophene'' solar cells using P3HT as electron donor and the above mentioned oligothiophenes as electron acceptor were fabricated and tested. The highest power conversion efficiency (PCE) of 1.31%% was achieved for DTSi-cored compound DTSi(THDCV) 2, whereas PTB7: DTSi(THDCV) 2 based device showed slightly higher PCE of 1.56%%. Electron mobilities of these three compounds were measured to be around 10 (5) cm(2) V (1) s (1) by space charge limited current method, which is much lower than that of PC61BM, and was considered as one of the reason for the low photovoltaic performance. (C) 2015 Elsevier B.V. All rights reserved.

3.An atomic finite element model for biodegradable polymers. Part 1. Formulation of the finite elements

Author:Gleadall, A;Pan, JZ;Ding, LF;Kruft, MA;Curco, D


Abstract:Molecular dynamics (MD) simulations are widely used to analyse materials at the atomic scale. However, MD has high computational demands, which may inhibit its use for simulations of structures involving large numbers of atoms such as amorphous polymer structures. An atomic-scale finite element method (AFEM) is presented in this study with significantly lower computational demands than MD. Due to the reduced computational demands, AFEM is suitable for the analysis of Young's modulus of amorphous polymer structures. This is of particular interest when studying the degradation of bioresorbable polymers, which is the topic of an accompanying paper. AFEM is derived from the inter-atomic potential energy functions of an MD force field. The nonlinear MD functions were adapted to enable static linear analysis. Finite element formulations were derived to represent interatomic potential energy functions between two, three and four atoms. Validation of the AFEM was conducted through its application to atomic structures for crystalline and amorphous poly(lactide). (C) 2015 Elsevier Ltd. All rights reserved.

4.Operation of 8-wavelength-radius 2-layer lenses

Author:Gray, D;Nikolic, N;Thornton, J


Abstract:Two competing 8-wavelength-radius 2-layer lens designs were identified in the literature. Both were analyzed by ray tracing and full wave simulation, as an initial step toward production by additive manufacturing for use at mm-wave frequencies. The conclusion of this initial study is that the relative permittivity 1.68 - 1.6 design appears to be best suited to production by laser sintering.

5.An Improved Brain Storm Optimization with Differential Evolution Strategy for Applications of ANNs

Author:Cao, ZJ;Hei, XH;Wang, L;Shi, YH;Rong, XF


Abstract:Brain Storm Optimization (BSO) algorithm is a swarm intelligence algorithm inspired by human being's behavior of brainstorming. The performance of BSO is maintained by the creating process of ideas, but when it cannot find a better solution for some successive iterations, the result will be so inefficient that the population might be trapped into local optima. In this paper, we propose an improved BSO algorithm with differential evolution strategy and new step size method. Firstly, differential evolution strategy is incorporated into the creating operator of ideas to allow BSO jump out of stagnation, owing to its strong searching ability. Secondly, we introduce a new step size control method that can better balance exploration and exploitation at different searching generations. Finally, the proposed algorithm is first tested on 14 benchmark functions of CEC 2005 and then is applied to train artificial neural networks. Comparative experimental results illustrate that the proposed algorithm performs significantly better than the original BSO.

6.Multiple strategies based orthogonal design particle swarm optimizer for numerical optimization

Author:Qin, QD;Cheng, S;Zhang, QY;Wei, YM;Shi, YH


Abstract:In the canonical partide swarm optimization (PSO), each particle updates its velocity and position by taking its historical best experience and its neighbors' best experience as exemplars and adding them together. Its performance is largely dependent on the employed exemplars. However, this learning strategy in the canonical PSO is inefficient when complex problems are being optimized. In this paper, Multiple Strategies based Orthogonal Design PSO (MSODPSO) is presented, in which the social-only model or the cognition-only model is utilized in each particle's velocity update, and an orthogonal design (OD) method is used with a small probability to construct a new exemplar in each iteration. In order to enhance the efficiency of OD method and obtain more efficient exemplar, four auxiliary vector generating strategies are designed. In addition, a global best mutation operator including non-uniform mutation and Gaussian mutation is employed to improve its global search ability. The MSODPSO can be applied to PSO with the global or local structure, yielding MSODPSO-G and MSODPSO-L algorithms, respectively. To verify the effectiveness of the proposed algorithms, a set of 24 benchmark functions in 30 and 100 dimensions are utilized in experimental studies. The proposed algorithm is also tested on a real-world economic load dispatch (ELD) problem, which is modelled as a non-convex minimization problem with constraints. The experimental results on the benchmark functions and ELD problems demonstrate that the proposed MSODPSO-G and MSODPSO-L can offer high-quality solutions. (C) 2015 Elsevier Ltd. All rights reserved.

7.Is the incipient Chinese civil society playing a role in regenerating historic urban areas? Evidence from Nanjing, Suzhou and Shanghai

Author:Verdini, G


Abstract:Urban regeneration in Western countries can count on a long-lasting tradition of experiences in which civil society has played a fundamental role in counterbalancing the system of power, resulting in profound urban governance readjustments. This has been the result of the increasing centrality of horizontal alliances between citizens and associations involved in urban affairs since the late 1960s in the West. Similar theoretical frameworks have been applied in China. However, these have frequently resulted in conceptual shortcuts that depict civil society as immature or lacking and the state as authoritarian. This paper will explore whether these categories are still entirely valid to urban regeneration in China. While the regime has traditionally prevented horizontal linkages of associations in urban governance (supporting their vertical integration to ensure a certain degree of soft control), there are signs of change. In particular, three cases of urban regeneration in historic areas will be used to discuss the changing role played by civil society in China. The ultimate goal is to examine whether horizontal linkages across groups of heterogeneous citizens are arising at the micro-level of urban governance. (C) 2015 Elsevier Ltd. All rights reserved.

8.Modelling conditional moments and correlation with the continuous hidden-threshold-skew-normal distribution

Author:Belhachemi, R;Rostan, P;Racicot, FE

Source:APPLIED ECONOMICS,2015,Vol.47

Abstract:A key issue in modelling conditional densities of returns of financial assets is the time-variation of conditional volatility. The classic econometric approach models volatility of returns with the generalized autoregressive conditional heteroscedasticity (GARCH) models where the conditional mean and the conditional volatility depend only on historical prices. We propose a new family of distributions in which the conditional distribution depends on a latent continuous factor with a continuum of states. The distribution has an interpretation in terms of a mixture distribution with time-varying mixing probabilities. The distribution parameters have economic interpretations in terms of conditional volatilities and correlations of the returns with the hidden continuous state. We show empirically that this distribution outperforms its main competitor, the mixed normal conditional distribution, in terms of capturing the stylized facts known for stock returns, namely, volatility clustering, leverage effect, skewness, kurtosis and regime dependence.

9.Artificial Bee Colony Algorithm with Time-Varying Strategy

Author:Qin, QD;Cheng, S;Zhang, QY;Li, L;Shi, YH


Abstract:Artificial bee colony (ABC) is one of the newest additions to the class of swarm intelligence. ABC algorithm has been shown to be competitive with some other population-based algorithms. However, there is still an insufficiency that ABC is good at exploration but poor at exploitation. To make a proper balance between these two conflictive factors, this paper proposed a novel ABC variant with a time-varying strategy where the ratio between the number of employed bees and the number of onlooker bees varies with time. The linear and nonlinear time-varying strategies can be incorporated into the basic ABC algorithm, yielding ABC-LTVS and ABC-NTVS algorithms, respectively. The effects of the added parameters in the two new ABC algorithms are also studied through solving some representative benchmark functions. The proposed ABC algorithm is a simple and easy modification to the structure of the basic ABC algorithm. Moreover, the proposed approach is general and can be incorporated in other ABC variants. A set of 21 benchmark functions in 30 and 50 dimensions are utilized in the experimental studies. The experimental results show the effectiveness of the proposed time-varying strategy.

10.Strong quantum confinement effect and reduced Frohlich exciton-phonon coupling in ZnO quantum dots embedded inside a SiO2 matrix

Author:Ning, JQ;Zheng, CC;Zhang, XH;Xu, SJ


Abstract:ZnO quantum dots (QDs) embedded in an amorphous SiO2 matrix were examined in depth by using variable-temperature photoluminescence (PL) and optical reflectance spectroscopies. Compared with ZnO bulk crystals, ZnO quantum dots with an average size of 4 nm exhibit a strong quantum confinement effect, evidenced by a large blue shift in both PL and reflectance peaks of excitons. More interestingly, a remarkably reduced long-range Frohlich interaction was revealed in ZnO QDs. These fascinating effects may make ZnO QDs a very appealing system in the fields of optoelectronics and others.

11.A Centralized Reactive Power Compensation System for LV Distribution Networks

Author:Chen, SX;Eddy, YSF;Gooi, HB;Wang, MQ;Lu, SF


Abstract:A centralized reactive power compensation system is proposed for low voltage (LV) distribution networks. It can be connected with any bus which needs reactive power. The current industry practice is to locally install reactive power compensation system to maintain the local bus voltage and power factor. By centralizing capacitor banks together, it can help to maintain bus voltages and power factors as well as reduce the power cable losses. Besides, the centralized reactive power system can be easily expanded to meet any future load increase. A reasonably sized centralized reactive power compensation system will be capable of meeting the requirements of the network and the optimization algorithm proposed in this paper can help to find this optimal size by minimizing the expected total cost (ETCH). Different load situations and their respective probabilities are also considered in the proposed algorithm. The concept of the centralized reactive power compensation system is applied to a local shipyard power system to verify its effectiveness. The results show that an optimally sized centralized reactive power system exists and is capable of maintaining bus voltages as well as reducing the power losses in the distribution network. A significant power loss reduction can be obtained at the optimal capacity of the centralized reactive power compensation system in the case study.

12.The spatial characteristics of global property investment in Seoul: A case study of the office market

Author:Kim, HM;O'Connor, KB;Han, SS


Abstract:As more and more countries liberalise their financial systems, capital has become increasingly mobile. These emerging capital flows and the accumulation of capital are mainly embodied in foreign direct investment. A new component is global property investment which is creating an internationalised office market and distinctive spatial patterns in global cities. Despite the increasing volume of foreign-owned property, as well as the popularity of the facilitating policies for cross-border capital flows into real estate, in both developed and developing countries, there has been little attention to the spatial characteristics of global property investment (GPI). Massive cross-border capital flows, associated with the decision of international property investors, will result in locally intensive changes. Understanding these changes will allow advice to refine and enhance sectoral and urban policy. The primary purpose of this study is, therefore, to explore the characteristics of GPI via the magnitude of the flows, global investors' location choice, links between property markets and office space markets, and government response to these outcomes. Seoul is used as case study because there is a fast growing foreign-owned office property sector along with city's growing integration with the global economy. (C) 2014 Elsevier Ltd. All rights reserved.

13.Stigma of Mental Illness: Social Distancing Attitudes among Registered Nurses in Australia

Author:Tan Kan Ku;Michael Ha;

Source:Proceedings of 2015 Workshop 12,2015,Vol.

Abstract:Background: Stigma of mental illness is often examined in social psychology and psychiatric rehabilitation using attitude studies. Participants of these studies are among health professionals and general public members. A common measure of stigma is using validated scale which measures the opinion o...

14.One-class kernel subspace ensemble for medical image classification (vol 2014, 17, 2014)

Author:Zhang, YG;Zhang, BL;Coenen, F;Xiao, JM;Lu, WJ


15.An Integrative Conceptual Framework of Business Model: The HeXie Management Theory Perspective

Author:LI Huijun;XI Youmin;GE Jing

Source:Chinese Journal of Management,2015,Vol.12


16.Supporting culturally and linguistically diverse students during clinical placement: strategies from both sides of the table

Author:O'Reilly, SL;Milner, J


Abstract:Background: Increasing proportions of Culturally and Linguistically Diverse (CALD) students within health professional courses at universities creates challenges in delivering inclusive training and education. Clinical placements are a core component of most health care degrees as they allow for applied learning opportunities. A research gap has been identified in regard to understanding challenges and strategies for CALD students in health professional placements. Methods: A key stakeholder approach was used to examine barriers and enablers experienced by CALD students in clinical placement. Semi-structured focus groups with healthcare students (n = 13) and clinical placement supervisors (n = 12) were employed. The focus groups were analysed using open coding and thematic analysis. Results: Three main barrier areas were identified: placement planning and preparation; teaching, assessment and feedback; and cultural and language issues. Potential solutions included addressing placement planning and preparation barriers, appropriate student placement preparation, pre-placement identification of higher risk CALD students, and diversity training for supervisors. For the barrier of teaching, assessment & feedback, addressing strategies were to: adapt student caseloads, encourage regular casual supervisor-student conversations, develop supportive placement delivery modes and structures, set expectations early, model the constructive feedback process, use visual aids, and tailor the learning environment to individual student needs. The enablers for cultural & language issues were to: build language and practical approaches for communication, raise awareness of the healthcare system (how it interacts with healthcare professions and how patients access it), and initiate mentoring programs. Conclusions: The findings suggest that teaching and learning strategies should be student-centred, aiming to promote awareness of difference and its impacts then develop appropriate responses by both student and teacher. Universities and partnering agencies, such as clinical training providers, need to provide an inclusive learning environment for students from multiple cultural backgrounds.

17.An exploration of techniques for off-screen content interaction in mobile devices

Author:Shen, T;Liang, HN;Liu, D;Man, KL


Abstract:This paper is an attempt to explore new ways for allowing interaction with mobile devices, such as smartphones and tablets. Mobile devices have become very popular in a relatively short time. Their popularity is mainly due to the portability and until very recently their ease-of-interaction through the touch-enabled screen when compared to older devices. Their portability comes with a trade-off: the small screen through which users can interact with their content. The small size screen can limit significantly the amount of content they can interact with, and also the manner in which this interaction is carried out. In this research, we explore the ways of extending the interaction space of these devices. We assess if, how well, and what mechanisms are possible for enabling users to interact with content located off the screen. In this paper, we report our approach and some early results of experiments we have conducted.

18.Local identity in the form-production process, using as a case study the multifunctional administrative city project (Sejong) in South Korea

Author:Choi, HS;Reeve, A


Abstract:This article argues that many of those changes to the built environment brought about through economic and cultural globalization have resulted in a blurring of national identities expressed through city form, worldwide, including South East and Far East Asian countries. As a reaction to this, local identity has emerged as a central concern among both academics and many built environment professionals for setting the twenty-first century urban development agenda. The focus of this article is to explore place-making in relation to the role of different actors within the form-production process, and the implications of globalization for local identity using as a case the new multifunctional administrative city of Sejong in South Korea. Evidence was collected using a testing survey that aimed at gaining a clear insight into the role of local identity from the perspectives of different key actors involved in the Sejong project; the survey focused on building up a comprehensive narrative of their knowledge, experience, and sense of identity and sustainability in relation to place identity in new place construction. This survey and the findings from it illustrate the importance of user participation in the decision-making process, in achieving social sustainability and the incorporation of local cultural resources. The findings summarized in this article reveal the current poor level of understanding and the limitations in delivering inclusive local identity within the urban design policies of Sejong, and how local identity and the needs of local culture could be incorporated, sustained and developed in contemporary new town development in the South East/Far East Asian context.

19.Fundamental groups, homology equivalences and one-sided h-cobordisms

Author:Su Yang;Ye Shengkui

Source:Science China. Mathematics,2015,Vol.58

Abstract:We give a necessary and sufficient condition for the fundamental group homomorphism of a map between CW-complexes (manifolds) to induce partial homology equivalences. As applications, we obtain characterizations of fundamental groups of homology spheres and Moore manifolds. Moreover, a classification of one-sided h-cobordism of manifolds up to diffeomorphisms is obtained, based on Quillen's plus construction with Whitehead torsions.

20.Multimodal Optimization Using Particle Swarm Optimization Algorithms: CEC 2015 Competition on Single Objective Multi-Niche Optimization

Author:Cheng, S;Qin, QD;Wu, Z;Shi, YH;Zhang, QY


Abstract:The aim of multimodal optimization is to locate multiple peaks/optima in a single run and to maintain these found optima until the end of a run. The results of seven variants of particle swarm optimization (PSO) algorithms on IEEE Congress on Evolutionary Computation (CEC) 2015 single objective multi-niche optimization problems are reported in this paper. The PSO algorithms include PSO with star structure, PSO with ring structure, PSO with four clusters structure, PSO with Von Neumann structure, social-only PSO with star structure, social-only PSO with ring structure, and cognition-only PSO. The experimental tests are conducted on fifteen benchmark functions. Based on the experimental results, the conclusions could be made that the PSO with ring structure performs better than the other PSO variants on multimodal optimization. To obtain good performance on the multimodal optimization problems, an algorithm needs to converge the candidate solutions to the global optima while keep the population diversity during whole search process.
Total 434 results found
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