12,163 research outputs found
Mobility: a double-edged sword for HSPA networks
This paper presents an empirical study on the performance of mobile High Speed Packet Access (HSPA, a 3.5G cellular standard) networks in Hong Kong via extensive field tests. Our study, from the viewpoint of end users, covers virtually all possible mobile scenarios in urban areas, including subways, trains, off-shore ferries and city buses. We have confirmed that mobility has largely negative impacts on the performance of HSPA networks, as fast-changing wireless environment causes serious service deterioration or even interruption. Meanwhile our field experiment results have shown unexpected new findings and thereby exposed new features of the mobile HSPA networks, which contradict commonly held views. We surprisingly find out that mobility can improve fairness of bandwidth sharing among users and traffic flows. Also the triggering and final results of handoffs in mobile HSPA networks are unpredictable and often inappropriate, thus calling for fast reacting fallover mechanisms. We have conducted in-depth research to furnish detailed analysis and explanations to what we have observed. We conclude that mobility is a double-edged sword for HSPA networks. To the best of our knowledge, this is the first public report on a large scale empirical study on the performance of commercial mobile HSPA networks
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Developing senior leaders and managers in the public sector: the case of the MPA for Chinese local government leaders
The paper explores how culture and education system affect leadership development for senior leaders from a local government via learning experiences in a different country. The research takes an interpretivist approach and adopts methods of semi-structured interviews and focus group discussions with students on a Masters' of Public Administration (MPA), who are senior leaders at their local government. The findings show that culture and education have a great impact on the outcomes of students learning from two aspects. Firstly education systems influence the approach of surface learning in the Chinese context. Secondly Confucianism contributes to the education system which indirectly affects students learning due to an issue of face. The findings present a valuable insight for both academics and practitioners in order to understand the significance of the relationship between culture and education as well leadership development
Grown-in defects and defects produced by 1-Me electron irradiated in Al0.3Ga0.7As P-N junction solar cells
Studies of grown-in defects and defects produced by the one-MeV electron irradiation in Al sub 0.3 Ga sub 0.7As p-n junction solar cells fabricated by liquid phase epitaxial (LPE) technique were made for the unirradiated and one-MeV electron irradiated samples, using DLTS and C-V methods. Defect and recombination parameters such as energy level, defect density, carrier capture cross sections and lifetimes were determined for various growth, annealing, and irradiation conditions
The effect of manganese oxide on the sinterability of hydroxyapatite
The sinterability of manganese oxide (MnO2) doped hydroxyapatite (HA) ranging from 0.05 to 1 wt% was investigated. Green samples were prepared and sintered in air at temperatures ranging from 1000 to 1400 °C. Sintered bodies were characterized to determine the phase stability, grain size, bulk density, hardness, fracture toughness and Young's modulus. XRD analysis revealed that the HA phase stability was not disrupted throughout the sintering regime employed. In general, samples containing less than 0.5 wt% MnO2 and when sintered at lower temperatures exhibited higher mechanical properties than the undoped HA. The study revealed that all the MnO2-doped HA achieved >99% relative density when sintered at 1100–1250 °C as compared to the undoped HA which could only attained highest value of 98.9% at 1150 °C. The addition of 0.05 wt% MnO2 was found to be most beneficial as the samples exhibited the highest hardness of 7.58 GPa and fracture toughness of 1.65 MPam1/2 as compared to 5.72 GPa and 1.22 MPam1/2 for the undoped HA when sintered at 1000 °C. Additionally, it was found that the MnO2-doped samples attained E values above 110 GPa when sintered at temperature as low as 1000 °C if compared to 1050 °C for the undoped HA
Less is More: Micro-expression Recognition from Video using Apex Frame
Despite recent interest and advances in facial micro-expression research,
there is still plenty room for improvement in terms of micro-expression
recognition. Conventional feature extraction approaches for micro-expression
video consider either the whole video sequence or a part of it, for
representation. However, with the high-speed video capture of micro-expressions
(100-200 fps), are all frames necessary to provide a sufficiently meaningful
representation? Is the luxury of data a bane to accurate recognition? A novel
proposition is presented in this paper, whereby we utilize only two images per
video: the apex frame and the onset frame. The apex frame of a video contains
the highest intensity of expression changes among all frames, while the onset
is the perfect choice of a reference frame with neutral expression. A new
feature extractor, Bi-Weighted Oriented Optical Flow (Bi-WOOF) is proposed to
encode essential expressiveness of the apex frame. We evaluated the proposed
method on five micro-expression databases: CAS(ME), CASME II, SMIC-HS,
SMIC-NIR and SMIC-VIS. Our experiments lend credence to our hypothesis, with
our proposed technique achieving a state-of-the-art F1-score recognition
performance of 61% and 62% in the high frame rate CASME II and SMIC-HS
databases respectively.Comment: 14 pages double-column, author affiliations updated, acknowledgment
of grant support adde
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Ethical innovation through Confucian teaching
This research explores innovation from an ethical perspective. With increasing number of Chinese business applying Confucius teaching into business management and employee training, this research explores the influence of Confucius values of harmony, familial collectivism and reciprocity. It aims to evaluate the teach ing of these key Confucius ethical values to staff in a private owned Chinese organisation, and its impact on business movement. Taking a case-study approach, this research is conducted in Good-ark, a private-owned semi-conductor manufacturing company in Suzhou, China. Data has been collected from semi-structured interviews and company's annual reports and training records. The results demonstrate that Confuci anism teaching enhances both employees' and managers' commitment towards the organisation. Through such ethical innovation, it reduces the organisation's employee turnover and forms a strong cohesion within the organisation, and improves individuals and organisational performance. Furthermore, Confucius teaching helps extend people's understanding of Confucius ethical values, which are further applied into a wider social context. The practical implication and limitations of the current research are also discussed
Quantum Walks on Trees with Disorder: Decay, Diffusion, and Localization
Quantum walks have been shown to have impressive transport properties
compared to classical random walks. However, imperfections in the quantum walk
algorithm can destroy any quantum mechanical speed-up due to Anderson
localization. We numerically study the effect of static disorder on a quantum
walk on the glued trees graph. For small disorder, we find that the dominant
effect is a type of quantum decay, and not quantum localization. For
intermediate disorder, there is a crossover to diffusive transport, while a
localization transition is observed at large disorder, in agreement with
Anderson localization on the Cayley tree.Comment: 12 pages, 13 figure
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The heterogeneous effects of CSR dimensions on financial performance -a new approach for CSR measurement
This paper investigates the differential effects of corporate social responsibility (CSR) dimensions on corporate financial performance (CFP) across sectors in China. This research uses a unique data set provided by China Stock Market and Accounting Research (CSMAR), showing expenditure on CSR programs from 568 Chinese publicly traded firm-year observations from 2008 to 2017. Compared to previous studies using scores produced by extra-financial rating agencies, this research quantifies CSR efforts by corporate expenditure on CSR practices, which offers quantitative and precise information in explaining the CSR-CFP link. The results show that the dimension of the environment has negative effects on financial performance in capital-intensive manufacturing industries. The impact of HR expenditure on CFP is negative in the tertiary sector and resource-intensive manufacturing industries. However, CSR investments in the community are positively related to financial performance in resource-intensive industries and other secondary sector (mining, construction, and utilities). Firms, in general, could gain benefits when spending more on business and financial stakeholders
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