147 research outputs found

    Adaptive Regularization for Class-Incremental Learning

    Full text link
    Class-Incremental Learning updates a deep classifier with new categories while maintaining the previously observed class accuracy. Regularizing the neural network weights is a common method to prevent forgetting previously learned classes while learning novel ones. However, existing regularizers use a constant magnitude throughout the learning sessions, which may not reflect the varying levels of difficulty of the tasks encountered during incremental learning. This study investigates the necessity of adaptive regularization in Class-Incremental Learning, which dynamically adjusts the regularization strength according to the complexity of the task at hand. We propose a Bayesian Optimization-based approach to automatically determine the optimal regularization magnitude for each learning task. Our experiments on two datasets via two regularizers demonstrate the importance of adaptive regularization for achieving accurate and less forgetful visual incremental learning

    Differentially Private Accelerated Optimization Algorithms

    Full text link
    We present two classes of differentially private optimization algorithms derived from the well-known accelerated first-order methods. The first algorithm is inspired by Polyak's heavy ball method and employs a smoothing approach to decrease the accumulated noise on the gradient steps required for differential privacy. The second class of algorithms are based on Nesterov's accelerated gradient method and its recent multi-stage variant. We propose a noise dividing mechanism for the iterations of Nesterov's method in order to improve the error behavior of the algorithm. The convergence rate analyses are provided for both the heavy ball and the Nesterov's accelerated gradient method with the help of the dynamical system analysis techniques. Finally, we conclude with our numerical experiments showing that the presented algorithms have advantages over the well-known differentially private algorithms.Comment: 28 pages, 4 figure

    Current conduction in Schottky barrier diodes with poly(propylene glycol)-b-polystyrene block copolymer interfacial layer

    Get PDF
    Polymeric materials have gained great importance in electron devices. There has been considerable number of studies on block copolymers due to enhanced features that appear after co-polymerization. In this study, poly (propylene glycol)-b-polystyrene block copolymer has been synthesized and Schottky barrier diodes (SBDs) have been fabricated with this block copolymer. Current-voltage (I-V) measurements have been conducted at room temperature in order to investigate electrical characteristics and current conductions governing in these SBDs. Series resistance and shunt resistance of the SBDs have been calculated using Ohm’s law. Ideality factor, reverse saturation current and zero-bias barrier height of the SBDs have been extracted from the forward-bias I-V data. Fabricated SBDs exhibited high rectifying ratio of the order 104. Also, current conduction mechanisms and the density of interface states in the SBDs have been investigated. Calculated values of density of interface states in the SBDs are on the order of 1013 which is acceptable for this kind of SBDs having polymeric interfacial layer

    Performance characterization of plywood panels bonded with melamine-urea-formaldehyde resin and cellulose nanofibril/borax as an additive

    Get PDF
    In this study, different loading levels of cellulose nanofibril and borax were added as reinforcement in melamine-urea-formaldehyde adhesive to enhance the performance properties of plywood panels as engineered wood composites. Physical properties (density, thickness swelling, water absorption, and moisture content), mechanical properties (modulus of rupture, modulus of elasticity, and bonding strength), and formaldehyde content were tested using relevant standards. The results showed that cellulose nanofibril and borax had a synergistic effect, resulting in improved physico-mechanical properties. The best results were obtained by combining 3 % cellulose nanofibril and borax. It was determined that the combination of cellulose nanofibril and borax reinforcement resulted in a significant improvement of around 15 % in the thickness swelling, water absorption, and moisture content of plywood panels. The combination of cellulose nanofibril and borax reinforcing resulted in a significant increase of around 26 % in the modulus of rupture and modulus of elasticity of plywood panels, with a bonding strength of around 47 %. The reinforcement technique did result in a 34 % decrease in free formaldehyde content. As a consequence, cellulose nanofibril and borax can be used as effective additives in the production of plywood panels to enhance their performance properties

    In vitro exposure to di-(2-ethylhexyl) phthalate (DEHP) stimulates spontaneous feline uterine contractions

    Get PDF
    Yildirim, Ebru/0000-0002-6289-0729; Kabakci, Ruhi/0000-0001-9131-0933; Elifoglu, Taha Burak/0000-0002-2302-6321WOS:000560988800020Di-(2-ethylhexyl) phthalate (DEHP) is widely used as a plasticizer in various products such as PVC-derived plastics, toys, packaging materials, cosmetics, and pharmaceuticals. This study aimed to investigate the effect of DEHP on spontaneous contractions of the feline uterus in vitro. Tubal 1-cm uterine samples prepared from 10, 9, and 12 uteri obtained from adult cats in estrus (n = 5), diestrus (n = 5), and interestrus (n = 5), respectively, after ovariohysterectomy were suspended in an isolated organ bath in aerated Krebs solution at 39 +/- 1 degrees C, and an initial 1 g tension was given. After 1 h equilibration of tissues, the spontaneous contractions were recorded for 10 min as control. The effects of solvent and DEHP (0.001-100 mu M) on contractions were then evaluated in terms of frequency and mean amplitude parameters. It was observed that DEHP had no effect on uterine contractions of cats in interestrus. However, DEHP significantly increased the mean amplitude of uterine contractions during the estrus and diestrus periods at concentrations of 1 mu M and 10 mu M, respectively, depending on the dose (P 0.05). 'this study, carried out for the first time in cats, showed that DEHP has a stimulatory effect on uterine contractions. We concluded that disruption of the uterine contractions, which are essential for physiological reproductive processes such as regular estrous cycles, sperm and zygote transport, implantation and continuation of pregnancy, by DEHP exposure may cause many reproductive problems

    A Learning Experience: Reflection

    Get PDF
    Öğrenme yaşantısından anlam çıkarmaya yardım edici yöntemlerden biri reflekşındır (reflection). Reflekşın, kişinin tüm düşüncelerini birproblem üzerinde yoğunlaştırması, bir konuyu ayrıntıyla düşünmesi ve irdelemesidir. Reflekşın yöntemi, öğrencilerin karşılaştıklarıdurumlarla ilgili eylemleri ya da eylemsizliklerinde kendilerini tanımalarına, eleştirel düşünmelerine, problem çözmelerine, sorumlulukalmalarına yardım etmektedir. Dokuz Eylül Üniversitesi (DEÜ) Hemşirelik Yüksekokulu'nda hemşirelik öğrencilerinin kişisel veprofesyonel gelişimini kolaylaştırmak amacıyla reflekşın yöntemi uygulanmaya başlanmıştır. Bu makalede reflekşın ile ilgili bilgiler vedeneyimlerin paylaşılması amaçlanmıştır. One of the methods which help us to infer from learning is reflection. Reflection is a way through which a person concentrates all hisattention on a certain problem, thinks about a topic in detail and examines it thoroughly. The reflection method helps students recognizethemselves, scrutinize, solve problems and take responsibility for being active or inactive in situations they encounter. In Dokuz EylülUniversity School of Nursing, in order to help nursing students improve their personal and professional development, the reflection methodhas been introduced. This article aims at sharing information and experiences related to reflection

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

    Get PDF
    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Advanced Renewable Nanomaterials for Sustainable Development

    No full text
    At the UN General Assembly, 193 United Nations Member States adopted the 2030 Agenda for Sustainable Development. This initiative is a global call to action. To achieve sustainable development, 17 Sustainable Development Goals (SDGs) have been defined, and nanoscience and nanotechnology play a critical role in these goals. Nanotechnology is regarded as an enabling technology since it involves the study, modification, manipulation, or creation of processes, structures, materials, or devices at the nanoscale. Nanotechnology is rapidly expanding in many areas, including aerospace, energy, automotive, medicine, and food, as well as in the textile, chemical, and electrical-electronic industries, and is expected to have a bright future. Nanomaterials are materials that are purposefully designed in a size range of 1 to 100 nm in 1, 2, or 3 dimensions. Nanotechnology and nanomaterials have a wide range of applications in every area of science and engineering, resulting in greater improvements. In particular, lignocellulose-based nanomaterials with a nanofibrillar structure are produced from natural resources and can be used in a wide range of commercial applications. The eco-friendliness, unique properties, and diverse capabilities of nanomaterials are being explored in order to develop innovative materials and applications in almost all areas. This review focused on nanotechnology and advanced renewable nanomaterials for sustainable development
    corecore