• 제목/요약/키워드: IGA

검색결과 88건 처리시간 0.023초

Numerical Analysis of Damping Effect of Liquid Film on Material in High Speed Liquid Droplet Impingement

  • Sasaki, Hirotoshi;Ochiai, Naoya;Iga, Yuka
    • International Journal of Fluid Machinery and Systems
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    • 제9권1호
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    • pp.57-65
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    • 2016
  • By high speed Liquid Droplet Impingement (LDI) on material, fluid systems are seriously damaged, therefore, it is important for the solution of the erosion problem of fluid systems to consider the effect of material in LDI. In this study, by using an in-house fluid/material two-way coupled method which considers reflection and transmission of pressure, stress and velocity on the fluid/material interface, high-speed LDI on wet/dry material surface is simulated. As a result, in the case of LDI on wet surface, maximum equivalent stress are less than those of dry surface due to damping effect of liquid film. Empirical formula of the damping effect function is formulated with the fluid factors of LDI, which are impingement velocity, droplet diameter and thickness of liquid film on material surface.

Optimal Production Design Using Genetic Algorithms (유전알고리즘을 이용한 최적생산설계)

  • 류영근
    • Journal of Korean Society of Industrial and Systems Engineering
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    • 제22권49호
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    • pp.115-123
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    • 1999
  • An optimization problem is to select the best of many possible design alternatives in a complex design space. Genetic algorithms, one of the numerous techniques to search optimal solution, have been successfully applied to various problems (for example, parameter tuning in expert systems, structural systems with a mix of continuous, integer and discrete design variables) that could not have been readily solved with more conventional computational technique. But, conventional genetic algorithms are ill defined for two classes of problems, ie., penalty function and fitness scaling. Therefore, this paper develops Improved genetic algorithms(IGA) to solve these problems. As a case study, numerical examples are demonstrated to show the effectiveness of the Improved genetic algorithms.

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Isogeometric analysis of gradient-enhanced damaged plasticity model for concrete

  • Xu, Jun;Yuan, Shuai;Chen, Weizhen
    • Computers and Concrete
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    • 제23권3호
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    • pp.171-188
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    • 2019
  • This study proposed a new and efficient 2D damage-plasticity model within the framework of Isogeometric analysis (IGA) for the geometrically nonlinear damage analysis of concrete. Since concrete exhibits complicated material properties, two internal variables are introduced to measure the hardening/softening behavior of concrete in tension and compression, and an implicit gradient-enhanced formulation is adopted to restore the well-posedness of the boundary value problem. The numerical results calculated by the model is compared with the experimental data of three benchmark problems of plain concrete (three-point and four-point bending single-notched beams and four-point bending double-notched beam) to illustrate the geometrical flexibility, accuracy, and robustness of the proposed approach. In addition, the influence of the characteristic length on the numerical results of each problem is investigated.

A Case of Nummular Eczema treated by Osuyu-tang based on Shanghanlun Provisions (『상한론(傷寒論)』 변병진단체계(辨病診斷體系)에 근거하여 오수유탕(吳茱萸湯) 투여 후 호전된 화폐상 습진 증례 1례)

  • Lim, Eun-kyo;Jeong, Jae-won
    • 대한상한금궤의학회지
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    • 제12권1호
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    • pp.149-159
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    • 2020
  • Objective: This study aimed to report the improvements of with nummular eczema treated using Osuyu-tang based on Shanghanlun provisions. Methods: According to the disease pattern identification diagnostic system based on the the patient was diagnosed with lesser-yin disease. The patient was treated with Osuyu-tang for 60 days. The severity of the patients' pruritus decreased, and changes in symptoms were assessed using visual analogue scale score and vIGA-ADTM Results: The patients' symptoms improved, pruritus decreased, and abrasion healed. Conclusions: The results suggest that the words on the 309th provision of Shanghanlun are a direct cause of nummular eczema.

Newly diagnosed pediatric immunoglobulin A nephropathy after vaccination against SARS-CoV-2: a case report

  • Do Young Kim;Hyung Eun Yim;Min Hwa Son;Kee Hwan Yoo
    • Childhood Kidney Diseases
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    • 제26권2호
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    • pp.91-96
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    • 2022
  • The messenger RNA-based vaccine for the coronavirus disease 2019 (COVID-19) may induce glomerulonephritis, including immunoglobulin A nephropathy (IgAN). New-onset IgAN triggered by vaccination against COVID-19 has been reported rarely, especially in children. Herein, we report a pediatric case of newly diagnosed IgAN after administration of the Pfizer vaccine for COVID-19. A 12-year-old girl was referred to our hospital for evaluation of gross hematuria after inoculation with the second dose of Pfizer's COVID-19 vaccine; she had no adverse effects after the first dose. At the time of admission, she showed heavy proteinuria and persistent hematuria. Kidney biopsy revealed an IgAN, and she was treated with an oral steroid and an angiotensin-converting enzyme inhibitor. Four months after discharge, the proteinuria and hematuria resolved completely.

Crevice Corrosion Properties of PWR Structure Materials Under Reductive Decontamination Conditions (환원제염조건에서 가압경수로 구조재료의 틈부식 특성)

  • Jung, Jun-Young;Park, Sang Yoon;Won, Hui Jun;Choi, Wang Kyu;Moon, Jei Kwon;Park, So Jin
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • 제12권3호
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    • pp.199-209
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    • 2014
  • Crevice corrosion tests were conducted to examine the corrosion properties of HYBRID (HYdrazine Base Reductive metal Ion Decontamination) which was developed to decontaminate the PWR primary coolant system. To compare the corrosion properties of HYBRID with commonly existing decontamination agents, oxalic acid (OA) and citric oxalic acid (CITROX) were also examined. Type 304 Stainless Steel (304 SS) and Alloy 600 which are major components of the primary coolant system in Pressurized Water Reactor (PWR) were evaluated. Crevice corrosion tests were conducted under very aggressive conditions to confirm quickly the corrosion properties of primary coolant system structure components which have high corrosion resistance. Pitting and IGA were occurred in crevice surface under OA and CITROX conditions. But localized corrosion was not observed under HYBRID condition. Very low corrosion rate of less than $1.3{\times}10^{-3}{\mu}m/h$ was observed under HYBRID condition for both materials. On the other hand, under OA condition, Alloy 600 indicated comparatively uniform corrosion rate of $4.0{\times}10^{-2}{\mu}m/h$ but 304 SS indicated rapid accelerated corrosion in lower case than pH 2.0. In case of HYBRID condition, general corrosion and crevice corrosion were scarcely occurred. Therefore, material integrity of HYBRID in decontamination of primary coolant system in pressurized water reactor (PWR) reactor was conformed.

A Clinical Study for the effect of cosmetic cream containing Samwhangsejegamibang Extracts on Atopic dermatitis patients (삼황세제 가미방 화장품의 아토피 피부염 환자에 대한 임상적 연구)

  • Joo, Hyun-A;Bae, Hyeon-Jin;Park, Min-Cheol;Baek, Sang-Chul;Hong, Seok-Hoon;Yang, Hyun-Ju;Cho, Hyun-Woo;Jung, Soo-Young;Cho, Jeong-Hee;Hwang, Chung-Yeon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • 제25권3호
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    • pp.129-149
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    • 2012
  • Objective : The purpose of this study is to investigate the effect of cosmetic cream containing Samwhangsejegamibang Extracts on Atopic dermatitis patients. Methods : A total of 51 patients who visited Wonkwang Oriental Medical Center from April 8th, 2011 to October 8th, 2011 were included in this study. In this study, the patients were treated with Samwhangsejegamibang (experimental group) and placebo group. We observed scorad index, IGA, moisture content of skin, oil content of skin, wrinkled skin and hematological examination for 4 weeks. Results : 1. Comparison of changes in Scorad Index, depending on the perspective, the experimental group showed a statistically significant decline than the placebo group. 2. Comparison of change in IGA, depending on the perspective, the experimental group showed a statistically significant decline than the placebo group. 3. Comparison of change in moisture content, oil content of skin and wrinkled skin, both the experimental group and the placebo group showed level elevation but there was no statistically significant change. 4. Comparison of change in IgE and Eosinophil, both the experimental group and the placebo group showed no statistical significance. Conclusions : Considering the above experiments, it is suggested that cosmetic cream containing Samwhangsejegamibang extracts have a positive effect on atopic dermatitis patients.

Emotion-based Video Scene Retrieval using Interactive Genetic Algorithm (대화형 유전자 알고리즘을 이용한 감성기반 비디오 장면 검색)

  • Yoo Hun-Woo;Cho Sung-Bae
    • Journal of KIISE:Computing Practices and Letters
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    • 제10권6호
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    • pp.514-528
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    • 2004
  • An emotion-based video scene retrieval algorithm is proposed in this paper. First, abrupt/gradual shot boundaries are detected in the video clip representing a specific story Then, five video features such as 'average color histogram' 'average brightness', 'average edge histogram', 'average shot duration', and 'gradual change rate' are extracted from each of the videos and mapping between these features and the emotional space that user has in mind is achieved by an interactive genetic algorithm. Once the proposed algorithm has selected videos that contain the corresponding emotion from initial population of videos, feature vectors from the selected videos are regarded as chromosomes and a genetic crossover is applied over them. Next, new chromosomes after crossover and feature vectors in the database videos are compared based on the similarity function to obtain the most similar videos as solutions of the next generation. By iterating above procedures, new population of videos that user has in mind are retrieved. In order to show the validity of the proposed method, six example categories such as 'action', 'excitement', 'suspense', 'quietness', 'relaxation', 'happiness' are used as emotions for experiments. Over 300 commercial videos, retrieval results show 70% effectiveness in average.

Characteristics of Clinical Trials in Korea for Atopic Dermatitis - Focus on ClinicalTrials.gov Registered Clinical Trials - (식약처 승인 아토피 피부염 의약품 국내 임상 시험의 특성 - ClinicalTrials.gov 등록 임상시험을 중심으로-)

  • Hwang, Mi-Lee;Ahn, Jae-Hyun;Jea, Ha-Kyung;Kim, Soo-Young;Jung, Hyun-A
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • 제32권2호
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    • pp.68-93
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    • 2019
  • Objective : This study summarized the characteristics of clinical trials for atopic dermatitis medicines approved by the Ministry of Food and Drug Safety(MFDS). This study may be a reference for the design of clinical trials of atopic dermatitis herbal medicine treatment which may be carried out later. Method : The characteristics of the clinical trial were analyzed for clinical trials registered with ClinicalTrials.gov, CRIS, and the Korea Health Industry Development Institute among the clinical trial approval statuses posted on the website of the MFDS. Result : 1. Clinical trial drugs were developed in various formulations such as oral medicines, injections, dermatologic agents, and similar proportions. Relatively little clinical trials were found for herbal medicine. 2. In the control evaluation test, most of the treatments for the control group were performed with placebo using Vehicle. 3. In most clinical trials, one intervention group was in the form of a parallel assignment with only one treatment. 4. The age of the subjects was 11 out of 28 studies including minors, and clinical trials targeting minors were also found to be significant. 5. In the case of atopic dermatitis, the cases of subacute chronic or atopic dermatitis more than 6 months or more than 1 year were often used. 6. Most clinical trials were divided into mild to moderate atopic dermatitis or moderate to severe atopic dermatitis. The SCORAD index, EASI, IGA, BSA, and NRS were used as the evaluation criteria. 7. Regulations for the drugs used prior to the trial period for the treatment of atopic dermatitis vary somewhat from one clinical trial to another. 8. IGA was used most often as a primary efficacy tool, and SCORAD index, EASI, and NRS were also used.

Multi-Objective Optimum Shape Design of Rotor-Bearing System with Dynamic Constraints Using Immune-Genetic Algorithm (면역.유전 알고리듬을 이용한 로터 베어링시스템의 다목적 형상최적설계)

  • Choe, Byeong-Geun;Yang, Bo-Seok
    • Transactions of the Korean Society of Mechanical Engineers A
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    • 제24권7호
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    • pp.1661-1672
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    • 2000
  • An immune system has powerful abilities such as memory, recognition and learning how to respond to invading antigens, and has been applied to many engineering algorithms in recent year. In this pap er, the combined optimization algorithm (Immune- Genetic Algorithm: IGA) is proposed for multi-optimization problems by introducing the capability of the immune system that controls the proliferation of clones to the genetic algorithm. The optimizing ability of the proposed combined algorithm is identified by comparing the result of optimization with simple genetic algorithm for two dimensional multi-peak function which have many local optimums. Also the new combined algorithm is applied to minimize the total weight of the shaft and the transmitted forces at the bearings. The inner diameter oil the shaft and the bearing stiffness are chosen as the design variables. The dynamic characteristics are determined by applying the generalized FEM. The results show that the combined algorithm and reduce both the weight of the shaft and the transmitted forces at the bearing with dynamic conatriants.