scholarly journals Quasi-periodic Geometry for Architectural Acoustics

2018 ◽  
Vol 15 (1) ◽  
pp. 42-61 ◽  
Author(s):  
Rima Ajlouni
Keyword(s):  
Periodic Structures ◽  
International Standards ◽  
New Wave ◽  
Periodic Surface ◽  
Sound Energy ◽  
New Class ◽  
Quantitative Analyses ◽  
Surface Profiles ◽  
Infinite Variety

The discovery of quasi-periodic atomic order in the crystalline state has uncovered an exciting new class of symmetries that has never been explored before. Because of their non-periodic translational order and self-similar properties, quasi-periodic structures offer unique opportunities for investigating questions related to their acoustical behavior. Their unique long-range non-periodic formations have the ability to diffuse and orchestrate the flow of sound energy in many unique ways; offering intriguing potential for innovating a new wave of optimized sound diffusers. One key limitation with available periodic diffusers is that their repeating logic creates repetitive energy loops, which significantly reduce their ability to uniformly disperse sound energy. Quasi-periodic geometry can mitigate such limitation. By encapsulating an infinite variety of distinct profiles in all directions, quasi-periodic surfaces can eliminate the formation of bundled or looped reflections; considerably enhancing the ability of the diffuser to uniformly disperse sound energy. To investigate this hypothesis, an experimental approach is used to simulate sound reflection patterns of the quasi-periodic surface profiles using a ray tracing method. Both qualitative and quantitative analyses are used to interpret the simulated results. The international Standards (ISO) metrics are used to validate the proposed approach and verify the results. Results show that the diffusion quality of the tested quasi-periodic surface is superior to the diffusion performance of the tested periodic surface.

scholarly journals InfoVAE: Balancing Learning and Inference in Variational Autoencoders

2019 ◽  
Vol 33 ◽  
pp. 5885-5892 ◽  
Author(s):  
Shengjia Zhao ◽  
Jiaming Song ◽  
Stefano Ermon
Keyword(s):  
Latent Variables ◽  
Performance Metrics ◽  
Generative Models ◽  
Qualitative And Quantitative ◽  
New Class ◽  
Latent Features ◽  
Quantitative Analyses ◽  
Effective Use

A key advance in learning generative models is the use of amortized inference distributions that are jointly trained with the models. We find that existing training objectives for variational autoencoders can lead to inaccurate amortized inference distributions and, in some cases, improving the objective provably degrades the inference quality. In addition, it has been observed that variational autoencoders tend to ignore the latent variables when combined with a decoding distribution that is too flexible. We again identify the cause in existing training criteria and propose a new class of objectives (Info-VAE) that mitigate these problems. We show that our model can significantly improve the quality of the variational posterior and can make effective use of the latent features regardless of the flexibility of the decoding distribution. Through extensive qualitative and quantitative analyses, we demonstrate that our models outperform competing approaches on multiple performance metrics

scholarly journals Quality Improvement of Laser-Induced Periodic Ripple Structures on Silicon Using a Bismuth-Indium Alloy Film

2021 ◽  
Vol 11 (2) ◽  
pp. 632
Author(s):  
Yao Chen ◽  
Yao Shan ◽  
Huatian Tu ◽  
Haotian Zhang ◽  
Rong He ◽  
...  
Keyword(s):  
Periodic Structures ◽  
Early Stage ◽  
Alloy Film ◽  
Pulse Number ◽  
Surface Structures ◽  
Large Area ◽  
Free Electrons ◽  
Periodic Surface ◽  
Laser Fluences

In this work, a new buffer layer material, a bismuth-indium (Bi-In) alloy, was utilized to improve the quality of large-area, laser-induced periodic ripple structures on silicon. Better-defined ripple structures and larger modification areas were obtained at different scanning speeds by pre-depositing a Bi-In film. The single-spot investigations indicated that ripple structures were much easier to form on silicon coated with the Bi-In film under laser fluences of 2.04 and 2.55 J/cm2 at a fixed pulse number of 200 in comparison with on bare silicon. A physical model in terms of the excellent thermal conductivity contributed by the free electrons in the Bi-In film homogenizing the thermal distribution caused by the laser irradiation in the early stage of the formation of laser-induced periodic surface structures was proposed to explain the above phenomena. The results show that the Bi-In film enabled a wider range of laser fluences to generate periodic structures and helped to form regular ripple structures on the silicon. In addition, the modulation effects of the laser fluence and pulse number on surface structures were studied experimentally and are discussed in detail.

The Changing Patterns of North Korea’s International Film Co-Productions Since the 1980s: A Global Value Chain Approach

2020 ◽  
pp. 83-108
Author(s):  
Moon Hwy-Chang ◽  
Wenyang Yin
Keyword(s):  
Value Chain ◽  
North Korea ◽  
Film Industry ◽  
International Standards ◽  
The Political ◽  
Global Value Chain ◽  
Comprehensive Understanding ◽  
Changing Patterns ◽  
Film Productions

Although North Korea is one of the most closed countries in the world, it has long been pursuing international cooperation with other countries in order to upgrade the quality of its film industry to international standards. Preceding studies on this topic have mainly focused on the political influences behind filmmaking in general and very few studies have exclusively dealt with North Korea’s international co-productions. In this respect, in order to develop a comprehensive understanding of the internalization strategy of North Korea’s film productions, this paper uses the global value chain as a framework for analysis. This approach helps understand the internationalization pattern of each value chain activity of film co-productions in terms of the film location and the methods for collaborating with foreign partners. By dividing the evolution of North Korea’s international co-productions into three periods since the 1980s, this paper finds that although North Korea has shown mixed results with different aspects of the film value chain, it has generally improved its internationalization over the three periods. This paper further provides strategic directions for North Korea by learning some of the successful Chinese experiences in the film sector regarding collaboration with foreign partners—to foster a win-win situation for all involved parties.

scholarly journals New diagonal micropolarizer arrays designed by an improved model in fourier domain

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jia Hao ◽  
Yan Wang ◽  
Kui Zhou ◽  
Xiaochang Yu ◽  
Yiting Yu
Keyword(s):  
Stokes Parameters ◽  
Fourier Domain ◽  
Extended Model ◽  
Reconstruction Accuracy ◽  
Polarization Imaging ◽  
New Class ◽  
Reconstruction Quality ◽  
Improved Design ◽  
Improved Model

AbstractThe design of micropolarizer array (MPA) patterns in Fourier domain provides an efficient approach to reconstruct and investigate the polarization information. Inspired by Alenin’s works, in this paper, we propose an improved design model to cover both 2 × N MPAs and other original MPAs, by which an entirely new class of MPA patterns is suggested. The performance of the new patterns is evaluated through Fourier domain analysis and numerical simulations compared with the existing MPAs. Particularly, we analyze the reconstruction accuracy of the first three Stokes parameters and degree of linear polarization (DoLP) in detail. The experimental results confirm that the 2 × 2 × 2 MPA provides the highest reconstruction quality of s0, s1, s2 and DoLP in terms of quantitative measures and visual quality, while the 3 × 3 diagonal MPA achieves the state-of-the-art best results in case of single-snapshot systems. The guidance of this extended model and new diagonal MPAs show its massive potential for the division of focal plane (DoFP) polarization imaging applications.

scholarly journals An assessment of the Armenian national midwifery curriculum as per international standards

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
L Aslanyan ◽  
S Sahakyan ◽  
V Petrosyan
Keyword(s):  
Poor Quality ◽  
International Standards ◽  
Assessment Tools ◽  
Global Competency ◽  
Midwifery Education ◽  
Study Team ◽  
Competency Based ◽  
Document Review ◽  
Provision Of Care

Abstract Background Literature suggests increasing evidence that incompetent midwifery education results in poor quality of care. The study compared and evaluated the level of compliance of the Armenian national criterion on midwifery with the global competency standards and developed recommendations for improvement. Methods The study team conducted a document review using a standardized checklist, which was adapted from the International Confederation of Midwives (ICM) core assessment tools. The document review explored if the main knowledge and skills/ability related elements of each ICM competency were separately covered by different modules of the national criterion using a scoring system with categories: not met, partially met, fully met and unspecified. Results Although the national criterion did not have specifically defined competencies, most of the elements required by the ICM were present as specific learning outcomes under different modules of the criterion. Midwifery program curriculum was described as intensive with unnecessarily heavy workload. Additionally, the document review reviled that most of the learning outcome defined in modules of the national criterion focused more on theoretical knowledge rather than practical skills and abilities. Overall, the ICM required competency in provision of care during pregnancy was the most comprehensively covered one in the national criterion, while the competency in facilitation of abortion related care was the lowest covered. National criterion did not highlight the importance of topics such as women's rights and health, principles of epidemiology, statistical methods of research, cultural, local and ethical beliefs. Conclusions The systematic comparison of the national criterion with internationally recognized essential competencies demonstrates significant gaps. The study team recommends revisions to the national criterion to make it competency based. Key messages Midwifery education criteria in Armenia did not reflect internationally accepted midwifery competency’s fundamental philosophy and values. Given the shortcomings of the current national midwifery education criterion, a comprehensive revision of the competencies of midwives in Armenia should be considered.

scholarly journals Supranational Assessment of the Quality of Probiotics: Collaborative Initiative between Independent Accredited Testing Laboratories

2021 ◽  
Vol 9 (7) ◽  
pp. 1456
Author(s):  
Jean-Pol Warzée ◽  
Marina Elli ◽  
Abdoulaye Fall ◽  
Daniela Cattivelli ◽  
Jean-Yves François
Keyword(s):  
Daily Basis ◽  
Qualitative Assessment ◽  
Close Collaboration ◽  
Quality Label ◽  
Accredited Laboratories ◽  
Quantitative Analyses ◽  
Quality Of Food ◽  
The Eu

Recent acquisitions about the role of the microbiota in the functioning of the human body make it possible to envisage an increasing use of beneficial microbes, and more particularly of probiotics as well as their metabolites, as nutritional supplements. National and EU authorities are engaged in assuring the safety and quality of food supplements and in defining rules to assess and communicate their efficacy on human health. The quality of probiotics, intended as strains’ identification, viability, and stability over time, is a crucial factor of credibility with consumers and health professionals. Analytical technologies for the quality control of probiotics must also be adapted to new preparations, such as those including new multistrains complex combinations. Accredited laboratories face this relevant challenge on a daily basis. Through its close collaboration with the laboratory commissioned to produce the specifications for its ESLP quality label (identification and quantitative analyses) together with its scientific committee, the ESLP has been focusing on this issue for 10 years. Recently, as part of the internationalization of the ESLP quality label, a new and unique initiative in Europe for the evaluation of the quality of probiotic preparations has been carried out. The collaboration between two accredited laboratories in Belgium and in Italy represented a concrete example of supranational collaboration in the assessment of the quality of probiotic preparations. Results show that both laboratories are in line as expected in terms of performance. Common approaches to the qualitative assessment of probiotic preparations, especially for complex and composite recipes, in terms of number of strains and included substances, should be encouraged and promoted all over the EU.

scholarly journals The association between Helicobacter pylori and obesity: a systematic review and meta-analysis of case–control studies

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Ali Baradaran ◽  
Hojat Dehghanbanadaki ◽  
Sara Naderpour ◽  
Leila Mohammadi Pirkashani ◽  
Abdolhalim Rajabi ◽  
...  
Keyword(s):  
Odds Ratio ◽  
Meta Analysis ◽  
Pooled Analysis ◽  
Case Control ◽  
Case Control Studies ◽  
Newcastle Ottawa Scale ◽  
Prevalence Of Obesity ◽  
Quantitative Analyses ◽  
H Pylori

Abstract Introduction The relationship between H. pylori infection and obesity development has remained controversial among various studies. The aim of this study was to clarify the pooled effect of H. pylori infection on the development of obesity and vice versa. Methods We searched international databases including Medline (PubMed), Web of sciences, Scopus, EMBASE, Cochrane, Ovid, and CINHAL to retrieve all case–control studies reporting the effect of H. pylori on obesity and vice versa, which had been published in English between January 1990 and June 2019. The quality of included studies was assessed by the Modified Newcastle–Ottawa Scale for Case–Control studies. The logarithm of the odds ratio (OR) and its standard error was used for the meta-analysis. Results Eight case–control studies with 25,519 participants were included for qualitative and quantitative analyses. The pooled analysis showed that obese participants had a higher risk of H. pylori infection than lean participants with an odds ratio of 1.46 (95%CI: 1.26, 1.68). Also, the pooled analysis revealed that participants infected by H. pylori had a higher risk of obesity than non-infected participants with an odds ratio of 1.01 (95%CI: 1.01, 1.02). Conclusion The results of this meta-analysis showed that there was a positive correlation between the risk of H. pylori infection and the prevalence of obesity development. Thus, H. pylori positive patients were more likely to be obese, and obese individuals had higher risks of H. pylori infection.

scholarly journals Novel Protein-Repellent and Antibacterial Resins and Cements to Inhibit Lesions and Protect Teeth

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Li Cao ◽  
Junling Wu ◽  
Qiang Zhang ◽  
Bashayer Baras ◽  
Ghalia Bhadila ◽  
...  
Keyword(s):  
Orthodontic Treatment ◽  
The Novel ◽  
Dental Resin ◽  
Biofilm Growth ◽  
New Class ◽  
Dental Resins ◽  
Wide Range ◽  
Oral Biofilms ◽  
One Year

Orthodontic treatment is increasingly popular as people worldwide seek esthetics and better quality of life. In orthodontic treatment, complex appliances and retainers are placed in the patients’ mouths for at least one year, which often lead to biofilm plaque accumulation. This in turn increases the caries-inducing bacteria, decreases the pH of the retained plaque on an enamel surface, and causes white spot lesions (WSLs) in enamel. This article reviews the cutting-edge research on a new class of bioactive and therapeutic dental resins, cements, and adhesives that can inhibit biofilms and protect tooth structures. The novel approaches include the use of protein-repellent and anticaries polymeric dental cements containing 2-methacryloyloxyethyl phosphorylcholine (MPC) and dimethylaminododecyl methacrylate (DMAHDM); multifunctional resins that can inhibit enamel demineralization; protein-repellent and self-etching adhesives to greatly reduce oral biofilm growth; and novel polymethyl methacrylate resins to suppress oral biofilms and acid production. These new materials could reduce biofilm attachment, raise local biofilm pH, and facilitate the remineralization to protect the teeth. This novel class of dental resin with dual benefits of antibacterial and protein-repellent capabilities has the potential for a wide range of dental and biomedical applications to inhibit bacterial infection and protect the tissues.

Inline Inspection: Both Effective Data Collection and Interpretation Needed to Achieve High Quality Reporting Results

2010 ◽  
Author(s):  
James R. Walker ◽  
Paul Mallaburn ◽  
Derek Balmer
Keyword(s):  
Financial Risk ◽  
Service Providers ◽  
Holistic Approach ◽  
Poor Quality ◽  
International Standards ◽  
Quality Reporting ◽  
Certification Standard ◽  
Consensus Standard ◽  
Inspection Data

Historically, pipeline operators have tended to place more weight on inline inspection tool specifications than on the inherent design and reporting capabilities of the service providers themselves. While internal collection of integrity data is very important, it’s imperative that vendors, also, have high levels of expertise and effective quality control systems in place to successfully analyze exceedingly high volumes of inspection data. The quality of inspection information is vital to assessing if a pipeline is fit for purpose now and/or into the future. Integrity managers attempting to reduce overall operating risk by making decisions based on inaccurate or poor quality reporting are in fact exposing their networks to greater safety and financial risk. Recognizing these risks and that inline inspection (ILI) is an overall system that needs to be formally qualified, operators and ILI service providers have collaborated to develop several international standards. The most recent is the umbrella API-1163 industry consensus standard, which is now being widely adopted, primarily in USA. This standard provides requirements and recommended practices for qualification of the entire ILI process. Two companion standards: ASNT In-line Personnel Qualification and Certification Standard No. ILI-PQ and NACE Recommended Practice In-Line Inspection of Pipelines RP0102 combine to address specific requirements for personnel who operate and analyze the results of ILI systems. In Europe, the Pipeline Operators Forum (POF) has, also, established specific requirements for ILI reporting processes and data formats. However, these standards do not define how operators and vendors must meet these requirements. To follow will be a story about how an ILI service provider embraced a holistic approach to address these standards’ requirements, in particular in the areas of data analysis, reporting, and dig verification due to their significant importance in assuring the final quality of its deliverables. A key outcome desired will be to provide operators with greater insight into what best practices and technologies ILI service providers should have embraced and invested in to insure reliable service delivery.

Improving the efficiency and quality of carrying out certification in the agrarian and industrial complex sphere

2021 ◽  
pp. 3-7
Author(s):  
V. A. Kazakova ◽  
V. A. Shinkevich ◽  
A. V. Dunayev
Keyword(s):  
International Standards ◽  
Industrial Complex ◽  
Complex Sphere

One of key problems of improvement of system of standardization is the greatest possible application of the international (regional) standards for implementation (confirmation) of compliance of production, services to the established requirements. In this regard harmonization with the international standards of three interstate standards directed on increase of efficiency and quality of carrying out certification of works (services) in the agrarian and industrial complex sphere is carried out: GOST "Diesels tractor and kombaynovy. Delivery in repair and release from repair. Specifications"; GOST "Tractors agricultural. Delivery in repair and release from repair. Specifications"; GOST "Combines self-propelled grain-harvesting and their assembly units. Delivery in repair and release from repair. Specifications".

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