High-Q double-disk microcavities for cavity optomechanics

We design a double-disk microcavity consisting of a pair of silica microdisks separated by a nanoscale gap region on a silicon chip for cavity optomechanics. We show that this type of photonic structure can provide a per-photon gradient force with a magnitude much larger than for scattering-force-based structures. Moreover, this device provides for nearly independent optimization of optical and mechanical properties. We present the processing details of fabricated devices

A Rule Based Taxonomy of Dirty Data

There is a growing awareness that high quality of datais a key to today’s business success and that dirty data existingwithin data sources is one of the causes of poor data quality. Toensure high quality data, enterprises need to have a process,methodologies and resources to monitor, analyze and maintainthe quality of data. Nevertheless, research shows that manyenterprises do not pay adequate attention to the existence of dirtydata and have not applied useful methodologies to ensure highquality data for their applications. One of the reasons is a lack ofappreciation of the types and extent of dirty data. In practice,detecting and cleaning all the dirty data that exists in all datasources is quite expensive and unrealistic. The cost of cleaningdirty data needs to be considered for most of enterprises. Thisproblem has not attracted enough attention from researchers. Inthis paper, a rule-based taxonomy of dirty data is developed. Theproposed taxonomy not only provides a mechanism to deal withthis problem but also includes more dirty data types than any ofexisting such taxonomies

A Comparison of Techniques for Name Matching

Information explosion is a problem for everyone nowadays. It is a great challenge to all kinds of businesses to maintain high quality of data in their information applications, such as data integration, text and web mining, information retrieval, search engine, etc. In such applications, matching names is one of the popular tasks. There are a number of name matching techniques available. Unfortunately, there is no existing name matching technique that performs the best in all situations. Therefore, a problem that every researcher or a practitioner has to face is how to select an appropriate technique for a given dataset. This paper analyses and evaluates a set of popular name matching techniques on several carefully designed different datasets. The experimental comparison confirms the statement that there is no clear best technique. Some suggestions have been presented, which can be used as guidance for researchers and practitioners to select an appropriate name matching technique in a given dataset

Mechanical oscillation and cooling actuated by the optical gradient force

In this work we combine the large per-photon optical gradient force with the sensitive feedback of a high quality factor whispering-gallery microcavity. The cavity geometry, consisting of a pair of silica disks separated by a nanoscale gap, shows extremely strong dynamical backaction, powerful enough to excite giant coherent oscillations even under heavily damped conditions (mechanical Q=4). In vacuum, the threshold for regenerative mechanical oscillation is lowered to an optical input power of only 270-nanoWatts, or roughly 1000 stored cavity photons, and efficient cooling of the mechanical motion is obtained with a temperature compression factor of 13-dB for 4-microWatts of dropped optical input power.Comment: 29 pages, 8 figure

The role of institutional quality on the performance in the export of coconut products

The literature that addresses the role of institutions in bilateral trade is extensive. However, research that links institutional quality to specific products and their different levels of value addition is lacking. In this study, we look into institutional quality, based on three indicators from the World Bank's world governance indicators, and its indicator-specific effects on bilateral coconut trade. In particular, we study coconut products with varying degrees of value addition. We use structural gravity models to measure how institutions affect the trade performance of the top 26 coconut producing countries to the top 15 importing economies over the years 1996-2016. Our results suggest that increased government effectiveness enhances trade of high-value products, whereas better voice and accountability scores decrease trade of coconut products with both levels of value addition. No clear trade effect is observed when two countries are more similar in each of the three indicators. We conclude that each indicator has different trade effects on each of the coconut product categories. We end by giving recommendations that will help to improve the coconut export performance in their respective countries and for future research