scholarly journals Improving the Effectiveness and Efficiency of Stochastic Neighbour Embedding with Isolation Kernel

2021 ◽  
Vol 71 ◽  
pp. 667-695
Author(s):  
Ye Zhu ◽  
Kai Ming Ting
Keyword(s):  
Large Scale ◽  
Computational Cost ◽  
Gaussian Kernel ◽  
Space Partitioning ◽  
Root Cause ◽  
Use Of Data ◽  
Local Point ◽  
Effectiveness And Efficiency ◽  
Insight Into

This paper presents a new insight into improving the performance of Stochastic Neighbour Embedding (t-SNE) by using Isolation kernel instead of Gaussian kernel. Isolation kernel outperforms Gaussian kernel in two aspects. First, the use of Isolation kernel in t-SNE overcomes the drawback of misrepresenting some structures in the data, which often occurs when Gaussian kernel is applied in t-SNE. This is because Gaussian kernel determines each local bandwidth based on one local point only, while Isolation kernel is derived directly from the data based on space partitioning. Second, the use of Isolation kernel yields a more efficient similarity computation because data-dependent Isolation kernel has only one parameter that needs to be tuned. In contrast, the use of data-independent Gaussian kernel increases the computational cost by determining n bandwidths for a dataset of n points. As the root cause of these deficiencies in t-SNE is Gaussian kernel, we show that simply replacing Gaussian kernel with Isolation kernel in t-SNE significantly improves the quality of the final visualisation output (without creating misrepresented structures) and removes one key obstacle that prevents t-SNE from processing large datasets. Moreover, Isolation kernel enables t-SNE to deal with large-scale datasets in less runtime without trading off accuracy, unlike existing methods in speeding up t-SNE.

scholarly journals Design and Demonstration of Large Scale Cu2O Photocathodes with Metal Grid Structure for Photoelectrochemical Water Splitting

Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 7422
Author(s):  
Min-Kyu Son
Keyword(s):  
Water Splitting ◽  
Large Scale ◽  
Grid Structure ◽  
Large Area ◽  
Intrinsic Conductivity ◽  
Metal Grid ◽  
Splitting System ◽  
Insight Into ◽  
Better Than

Upscaling of photoelectrode for a practical photoelectrochemical (PEC) water splitting system is still challenging because the PEC performance of large-scale photoelectrode is significantly low, compared to the lab scale photoelectrode. In an effort to overcome this challenge, sputtered gold (Au) and copper (Cu) grid lines were introduced to improve the PEC performance of large-scale cuprous oxide (Cu2O) photocathode in this work. It was demonstrated that Cu grid lines are more effective than Au grid lines to improve the PEC performance of large-scale Cu2O photocathode because its intrinsic conductivity and quality of grid lines are better than ones containing Au grid lines. As a result, the PEC performance of a 25-cm2 scaled Cu2O photocathode with Cu grid lines was almost double than one without grid lines, resulting in an improved charge transport in the large area substrate by Cu grid lines. Finally, a 50-cm2 scaled Cu2O photocathode with Cu grid lines was tested in an outdoor condition under natural sun. This is the first outdoor PEC demonstration of large-scale Cu2O photocathode with Cu grid lines, which gives insight into the development of efficient upscaled PEC photoelectrode.

scholarly journals A Survey of Methods for Gas-Lift Optimization

2012 ◽  
Vol 2012 ◽  
pp. 1-16 ◽  
Author(s):  
Kashif Rashid ◽  
William Bailey ◽  
Benoît Couët
Keyword(s):  
Large Scale ◽  
Optimization Problem ◽  
Multivariate Optimization ◽  
Flow Lines ◽  
Single Well ◽  
Large Scale Networks ◽  
Optimization Schemes ◽  
Gas Lift ◽  
Insight Into

This paper presents a survey of methods and techniques developed for the solution of the continuous gas-lift optimization problem over the last two decades. These range from isolated single-well analysis all the way to real-time multivariate optimization schemes encompassing all wells in a field. While some methods are clearly limited due to their neglect of treating the effects of inter-dependent wells with common flow lines, other methods are limited due to the efficacy and quality of the solution obtained when dealing with large-scale networks comprising hundreds of difficult to produce wells. The aim of this paper is to provide an insight into the approaches developed and to highlight the challenges that remain.

scholarly journals Management of Stress in Culture Fish

2020 ◽  
Vol 11 (6) ◽  
pp. 607-612
Author(s):  
T. Suguna ◽  
Keyword(s):  
Large Scale ◽  
Age Groups ◽  
Stocking Density ◽  
Economic Loss ◽  
Small Scale ◽  
Root Cause ◽  
Disease Occurrence ◽  
Physico Chemical ◽  
Controlling Measures

Over the last three decades, the commercial aquaculture has experienced spectacular growth. Many species have gone from small scale regional production to large scale global production. Concomitant with the rapid growth there also has been the increased occurrence of problems that accompany all agricultural endeavours. All the problems are stress influenced leading to diseases, impacting the profitability of the industries. In aquaculture also inspite of the unprecedented development of the intensified culture practices many economical problems have arise that are threatening the sustainability of culture systems. The root cause for all is stress. The word, “stress” is very common butreflects vast effective results. It is an invisible factor, influencing the survivality, growth, reproduction, production in culture fish especially. It is much easier for diseases to proliferate in the culture environment than in wild. Defining what levels of stressors are normal and acceptable is not easy. A level of stressor that is problematic under one set of environmental conditions might not be the same under another. The susceptibility of disease occurrence differs within species and age groups. Different stress factor such as inadequate physico chemical and microbial quality of culture water, poor nutritional stems and high stocking density can cause infection by opportunistic pathogens. In aquaculture, the stress plays major role on production, productivity, sustainability of the culture, economic loss and degradation of economic standards. A summation of causes for the acute and chronic stressors will enlighten the aqua farmers, scientists and fishery officials in designing environmentally friendly controlling measures, in obtaining higher yields.

The Passion Plays in Tegelen: An investigation into the function of a passion play

1991 ◽  
Vol 16 (1) ◽  
pp. 29-39
Author(s):  
Robert L. Erenstein
Keyword(s):  
Large Scale ◽  
World View ◽  
External Interference ◽  
Passion Plays ◽  
Passion Play ◽  
Cultural Phenomenon ◽  
Theatrical Performance ◽  
And Performance ◽  
Insight Into

Passion plays in Europe exhibit a great many similarities as far as general content and presentation are concerned. I do not really think it is relevant for the non-Dutch reader, therefore, to delve too deeply into the specifics of content and presentation with regard to the passion plays in Tegelen in Limburg, the southernmost province of the Netherlands. However, a great deal of the external interference surrounding the passion plays in Tegelen, has also been experienced by the organisers of numerous passion plays in Europe. Therefore, rather than discuss their content, it is far more interesting to investigate these passion plays through their development from 1931 when they began. Through this we can gain insight into the manner in which a social and cultural phenomenon such as a passion play can play a role in the maintenance and even the imposition of a particular world view. For the quality of the text and performance of passion plays are less important than the manner in which a community, usually a small one, driven by a communal ideal, expresses religious feelings which tens of thousands of spectators share. In such a performance there is communal activity with a ritual character. Performers are frequently anonymous and spectators and critics set aside any criticism of individual acting or the text because a passion play entails more than merely a large-scale theatrical performance by enthusiastic amateurs.

scholarly journals Optimizing schedules for the VLBI global observing system

2020 ◽  
Vol 94 (1) ◽  
Author(s):  
Matthias Schartner ◽  
Johannes Böhm
Keyword(s):  
Large Scale ◽  
Optimization Problem ◽  
Very Long Baseline Interferometry ◽  
Proper Selection ◽  
Long Baseline ◽  
Weight Factors ◽  
Highly Correlated ◽  
Insight Into ◽  
Selection Of

AbstractVery long baseline interferometry (VLBI) scheduling is a challenging optimization problem. With the development of the new VLBI global observing system (VGOS) consisting of smaller but very fast slewing antennas, new opportunities arise. In this work, we give a deep insight into optimized VGOS scheduling using a newly developed VLBI scheduling software called VieSched, and we show how different scheduling parameters and approaches affect the precision of geodetic results. Therefore, the results of over one thousand generated schedules and over one million simulated sessions are analyzed. The simulations reveal that the most important parameters to optimize VGOS schedules with VieSched are the so-called weight factors. A proper selection of individually optimized weight factors can improve the quality of a schedule significantly. It is shown that the values of the weight factors used to generate the schedule are highly correlated with the expected precision of the geodetic parameters. We highlight the benefit of selecting schedules based on large-scale Monte Carlo simulations and show why scheduling statistics like the number of observations or the sky-coverage are not necessarily the best metric to evaluate schedules.

EFFICIENT LARGE-SCALE SERVICE CLUSTERING VIA SPARSE FUNCTIONAL REPRESENTATION AND ACCELERATED OPTIMIZATION

2013 ◽  
Vol 22 (04) ◽  
pp. 1341001 ◽  
Author(s):  
QI YU
Keyword(s):  
Web Services ◽  
Service Discovery ◽  
Large Scale ◽  
Computational Cost ◽  
Functional Representation ◽  
Massive Number ◽  
Effectiveness And Efficiency ◽  
Service Clustering ◽  
Service Data ◽  
High Computational Cost

Clustering techniques offer a systematic approach to organize the diverse and fast increasing Web services by assigning relevant services into homogeneous service communities. However, the ever increasing number of Web services poses key challenges for building large-scale service communities. In this paper, we tackle the scalability issue in service clustering, aiming to accurately and efficiently discover service communities over very large-scale services. A key observation is that service descriptions are usually represented by long but very sparse term vectors as each service is only described by a limited number of terms. This inspires us to seek a new service representation that is economical to store, efficient to process, and intuitive to interpret. This new representation enables service clustering to scale to massive number of services. More specifically, a set of anchor services are identified that allows each service to represent as a linear combination of a small number of anchor services. In this way, the large number of services are encoded with a much more compact anchor service space. Despite service clustering can be performed much more efficiently in the compact anchor service space, discovery of anchor services from large-scale service descriptions may incur high computational cost. We develop principled optimization strategies for efficient anchor service discovery. Extensive experiments are conducted on real-world service data to assess both the effectiveness and efficiency of the proposed approach. Results on a dataset with over 3,700 Web services clearly demonstrate the good scalability of sparse functional representation and the efficiency of the optimization algorithms for anchor service discovery.

scholarly journals Perceived quality management of educational services from the perspective of parents as stakeholders

2020 ◽  
Vol 4 (1) ◽  
pp. 41-52
Author(s):  
Lidija Kodrin
Keyword(s):  
Qualitative Research ◽  
Focus Group ◽  
Group Discussion ◽  
Perceived Quality ◽  
Educational Services ◽  
Educational Organizations ◽  
Gap Model ◽  
Effectiveness And Efficiency ◽  
Insight Into

Introduction. Quality is crucial for education as competition in the education services market is steadily intensifying. The critical attitude of participants in education requires improving the quality of work of educational organizations, their effectiveness and efficiency. Those educational organizations wishing to maintain or improve their position in the market are forced to work intensively to improve their work and increase their responsiveness to the needs of users. Secondary schools need to be aware that the ultimate arbiter of quality of the educational services they provide are stakeholders (parents) as one of primary customers of educational services. Aim and tasks. The objective of the study is to determine the dimensions of the expected and perceived quality of educational services from parents’ perspective and to identify if they coincide with the dimensions in the classical gap model. Qualitative research that provides insight into the  perspectives of parents on the quality of educational services and their understanding of the quality concepts was conducted. Results. Based on the results of preliminary qualitative research, we have drawn up dimensions of perceived and expected quality of educational services: environment, reliability, responsiveness, assurance and empathy. The dimensions obtained through the focus group discussion of parents correspond to the dimensions in the classical GAP Model of Service Quality. Elements of assessment of parents' expectations and perception of the quality of educational services are considered (dimensions, tangibles, reliability, responsiveness, assurance, empathy). Conclusions. The objective of this study was to identify the expectations and perceptions of parents as primary customers of educational services. The insight into the perspectives of parents on the quality of educational services and their understanding of the quality concepts was obtained with qualitative. Further on the dimensions of the expected and perceived quality of educational services from parents’ perspective were identified. It was confirmed that the dimensions identified in this research coincide with the dimensions in the classical gap model. Based on the results of the parents’ focus group and the original SERVQUAL instrument the questionnaire was designed and used in further research.

scholarly journals High mobility SiMOSFETs fabricated in a full 300 mm CMOS process

2021 ◽  
Author(s):  
Timothy Camenzind ◽  
Asser Elsayed ◽  
Fahd Mohiyaddin ◽  
Ruoyu Li ◽  
Stefan Kubicek ◽  
...  
Keyword(s):  
Large Scale ◽  
Quantum Information Processing ◽  
High Mobility ◽  
Cmos Process ◽  
High Quality ◽  
Si Substrates ◽  
Material Optimization ◽  
Underlying Mechanisms ◽  
Insight Into

Abstract The quality of the semiconductor-barrier interface plays a pivotal role in the demonstration of high quality reproducible quantum dots for quantum information processing. In this work, we have measured SiMOSFET Hall bars on undoped Si substrates in order to investigate the device quality. For devices fabricated in a full CMOS process and of very thin oxide below a thickness of \unit[10]{nm}, we report a record mobility of \unit[$17.5\times 10^{3}$]{cm$^2$/Vs} indicating a high quality interface, suitable for future qubit applications. We also study the influence of gate materials on the mobilities and discuss the underlying mechanisms, giving insight into further material optimization for large scale quantum processors.

scholarly journals decorate: differential epigenetic correlation test

2020 ◽  
Vol 36 (9) ◽  
pp. 2856-2861
Author(s):  
Gabriel E Hoffman ◽  
Jaroslav Bendl ◽  
Kiran Girdhar ◽  
Panos Roussos
Keyword(s):  
Large Scale ◽  
Statistical Tests ◽  
Computational Cost ◽  
R Package ◽  
Supplementary Information ◽  
Expression Data ◽  
Correlation Test ◽  
Disease Biology ◽  
Genome Wide ◽  
Insight Into

Abstract Motivation Identifying correlated epigenetic features and finding differences in correlation between individuals with disease compared to controls can give novel insight into disease biology. This framework has been successful in analysis of gene expression data, but application to epigenetic data has been limited by the computational cost, lack of scalable software and lack of robust statistical tests. Results Decorate, differential epigenetic correlation test, identifies correlated epigenetic features and finds clusters of features that are differentially correlated between two or more subsets of the data. The software scales to genome-wide datasets of epigenetic assays on hundreds of individuals. We apply decorate to four large-scale datasets of DNA methylation, ATAC-seq and histone modification ChIP-seq. Availability and implementation decorate R package is available from https://github.com/GabrielHoffman/decorate. Supplementary information Supplementary data are available at Bioinformatics online.

Creating Contemporary Ritual: The Choreography of Lin Lee-Chen and Anna Halprin

2008 ◽  
Vol 40 (S1) ◽  
pp. 252-262
Author(s):  
Sheenru Yong
Keyword(s):  
Large Scale ◽  
Close Reading ◽  
Ritual Performance ◽  
Distinctive Features ◽  
Performance Quality ◽  
The Earth ◽  
And Performance ◽  
Insight Into ◽  
Shed Light

A study and comparison of works by two creators of ritual performance—Anna Halprin and Lin Lee-Chen—provide insight into Richard Schechner's efficacy-entertainment continuum as well as how ritual manifests in contemporary performance. Through a close reading of the structure and performance quality of Lin's Miroirs de Vie (Jiao) and Halprin's Circle the Earth “Dancing with Life on the Line,” I look at both artist's efforts and results in creating ritual performance and illustrate what I believe to be their distinctive features. Contextualization of the work and the artists' intentions shed light on the possibility or scope of change effected by their creations. While Lin's highly stylized large-scale dance-dramas in many senses cannot be compared to Halprin's nature-oriented participatory community rituals, commonalities in these two works show a strong emphasis on bodily experience, indicating embodiment as fundamental in creating transformative performance.

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