Hong Kong Polytechnic University

About: Hong Kong Polytechnic University is a education organization based out in Hong Kong, China. It is known for research contribution in the topics: Tourism & Population. The organization has 29633 authors who have published 72136 publications receiving 1956312 citations. The organization is also known as: HKPU & PolyU.

Automatic Pixel-Level Crack Detection and Measurement Using Fully Convolutional Network

Abstract: The spatial characteristics of cracks are significant indicators to assess and evaluate the health of existing buildings and infrastructures However, the current manual crack description

On the generalization of fuzzy rough sets

Abstract: Rough sets and fuzzy sets have been proved to be powerful mathematical tools to deal with uncertainty, it soon raises a natural question of whether it is possible to connect rough sets and fuzzy sets. The existing generalizations of fuzzy rough sets are all based on special fuzzy relations (fuzzy similarity relations, T-similarity relations), it is advantageous to generalize the fuzzy rough sets by means of arbitrary fuzzy relations and present a general framework for the study of fuzzy rough sets by using both constructive and axiomatic approaches. In this paper, from the viewpoint of constructive approach, we first propose some definitions of upper and lower approximation operators of fuzzy sets by means of arbitrary fuzzy relations and study the relations among them, the connections between special fuzzy relations and upper and lower approximation operators of fuzzy sets are also examined. In axiomatic approach, we characterize different classes of generalized upper and lower approximation operators of fuzzy sets by different sets of axioms. The lattice and topological structures of fuzzy rough sets are also proposed. In order to demonstrate that our proposed generalization of fuzzy rough sets have wider range of applications than the existing fuzzy rough sets, a special lower approximation operator is applied to a fuzzy reasoning system, which coincides with the Mamdani algorithm.

High-performance hole-extraction layer of sol-gel-processed NiO nanocrystals for inverted planar perovskite solar cells.

Abstract: Hybrid organic/inorganic perovskite solar cells have been rapidly evolving with spectacular successes in both nanostructured and thin-film versions. Herein, we report the use of a simple sol-gel-processed NiO nanocrystal (NC) layer as the hole-transport layer in an inverted perovskite solar cell. The thin NiO NC film with a faceted and corrugated surface enabled the formation of a continuous and compact layer of well-crystallized CH3 NH3 PbI3 in a two-step solution process. The hole-extraction and -transport capabilities of this film interfaced with the CH3 NH3 PbI3 film were higher than those of organic PEDOT:PSS layers. The cell with a NiO NC film with a thickness of 30-40 nm exhibited the best performance, as a thinner layer led to a higher leakage current, whereas a thicker layer resulted in a higher series resistance. With the NiO film, we observed a cell efficiency of 9.11 %, which is by far the highest reported for planar perovskite solar cells based on an inorganic hole-extracting layer.

A comparison of the effects of problem-based learning and lecturing on the development of students' critical thinking.

Abstract: Background Educational approaches are thought to have facilitative or hindering effects on students' critical thinking development. The aim of this study was to compare the effects of problem-based learning (PBL) and lecturing approaches on the development of students' critical thinking. Methods All 79 Year 1 undergraduate nursing students at a university in Hong Kong were randomly assigned to 1 of 2 parallel courses delivered by either PBL (n = 40) or lecturing (n = 39) over 1 academic year. The primary outcome measure was students' critical thinking disposition as measured by the California Critical Thinking Disposition Inventory (CCTDI). Individual interviews were also conducted to elicit the students' perceptions of their learning experience. Data were collected at 4 timepoints spanning 3 years. Results The overall CCTDI and subscale scores for the PBL group were not significantly different from those of the lecture group at the first timepoint (pretest). Compared with lecture students, PBL students showed significantly greater improvement in overall CCTDI (P = 0.0048), Truthseeking (P = 0.0008), Analyticity (P = 0.0368) and Critical Thinking Self-confidence (P = 0.0342) subscale scores from the first to the second timepoints; in overall CCTDI (P = 0.0083), Truthseeking (P = 0.0090) and Analyticity (P = 0.0354) subscale scores from the first to the third timepoints; and in Truthseeking (P = 0.0173) and Systematicity (P = 0.0440) subscale scores from the first to the fourth timepoints. Conclusions There were significant differences in the development of students' critical thinking dispositions between those who undertook the PBL and lecture courses, respectively.