Multimode optical feedback dynamics in InAs/GaAs quantum dot lasers emitting exclusively on ground or excited states: transition from short- to long-delay regimes

© 2018 Optical Society of America. Users may use, reuse, and build upon the article, or use the article for text or data mining, so long as such uses are for non-commercial purposes and appropriate attribution is maintained. All other rights are reserved.The optical feedback dynamics of two multimode InAs/GaAs quantum dot lasers emitting exclusively on sole ground or excited lasing states is investigated. The transition from long- to short-delay regimes is analyzed, while the boundaries associated to the birth of periodic and chaotic oscillations are unveiled to be a function of the external cavity length. The results show that depending on the initial lasing state, different routes to chaos are observed. These results are of importance for the development of isolator-free transmitters in short-reach networks

Variable selection based on entropic criterion and its application to the debris-flow triggering

We propose a new data analyzing scheme, the method of minimum entropy analysis (MEA), in this paper. New MEA provides a quantitative criterion to select relevant variables for modeling the physical system interested. Such method can be easily extended to various geophysical/geological data analysis, where many relevant or irrelevant available measurements may obscure the understanding of the highly complicated physical system like the triggering of debris-flows. After demonstrating and testing the MEA method, we apply this method to a dataset of debris-flow occurrences in Taiwan and successfully find out three relevant variables, i.e. the hydrological form factor, numbers and areas of landslides, to the triggering of observed debris-flow events due to the 1996 Typhoon Herb.Comment: 9 pages and 4 table

From Isovist to Spatial Perception: Wayfinding in Historic Quarter

Based on the assumption that human behaviours are mainly affected by physical and animate environments, this empirical research takes the changeful and complex historical district in Tainan to observe wayfinding behaviours. An a priori analysis of the isovist fields is conducted to identify spatial characteristics. Three measures, the relative area, convexity, and circularity, are applied to scrutinize the possible stopping points, change of speed, and route choices. Accordingly, an experiment is carried out to observe spatial behaviours and different influences of social stimuli. Results show that social interactions afford groups and pairs to perform better than individual observers in wayfinding.© 2016. The Authors. Published for AMER ABRA by e-International Publishing House, Ltd., UK. This is an open access article under the CC BY-NC-ND license (http://creative commons.org/licenses/by-nc-nd/4.0/).Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.Keywords: wayfinding; isovist; spatial perception and social stimuli; historic quarte

THE INFLUENCE OF PRODUCT PRESENTATION MODE AND ACADEMIC MAJOR ON THE MOTIVATION OF HAPTIC

Purpose of the study: This study was aimed to investigate the effect of product presentation mode and education background of the subject on the willingness of touch, preferences and visual imagery. Methodology: A total of 60 students were recruited to participate. The independent variables included product presentation mode (physical products, backgrounds removed image, scenario photo) and academic major of the subject (design major or management major). Three different kind dependent variables were measured in the study. On physical product condition, one sample was placed in front of subjects at a time. Both backgrounds removed image and scenario photo conditions, the subjects view experimental photos through a 22-inch LCD screen. They watched the sample item for 10 seconds and then were asked to assess the subjective questionnaire. Main Findings: The study results showed that when watching a physical product, the motivation of touch was greatest. The scenario photo generated more positive feelings and resulted in higher preference rating. The willingness of touch, preference and sensory ratings of management major students were higher than design major students. Applications of this study: The findings of this study can serve as a reference for enterprises to properly present products on web pages in order to increase consumers’ motivation to touch and preference. Novelty/Originality of this study: This study reinforces construction of a model of motivation to touch, and find that product presentation mode significant affect motivation to touch, preference and novelty feeling

Coronary Artery Ectasia Presenting With Recurrent Inferior Wall Myocardial Infarction

AbstractCoronary ectasia presenting as a recurrent inferior myocardial infarction has rarely been reported in the literature. Herein, we report a 61-year-old man who presented with persistent chest pain accompanied by ST segment elevation in the inferior ECG leads. Coronary angiography showed ectasia of the right coronary artery (RCA) and total occlusion from the middle RCA. Two stents were implanted separately in the middle and distal RCA. The patient was readmitted due to recurrent inferior wall infarction 15 months after discharge. He underwent primary percutaneous coronary intervention again, and coronary angiography showed massive thrombosis and in-stent re-stenosis. The thrombosis and re-stenosis were successfully treated using balloon angioplasty. The patient was discharged under medical therapy with aspirin and clopidogrel. There were no anginal symptoms during the 3 years of follow up