• Title/Summary/Keyword: effective models

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인천해안지역의 식물군집구조 분석을 통한 해안림 식재모델 연구(I) - 곰솔림과 소나무림을 대상으로 - (The Planting Models of Maritime Forest by the Plant Community Structure Analysis in the Seaside, Incheon - A Case Study on Pinus thunbergil Community and P. densiflora Community-)

  • 권전오;이경재;장상항
    • 한국조경학회지
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    • 제31권6호
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    • pp.53-63
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    • 2004
  • Planting models for restoration forest on the seaside have been demanded because coastal reclaimed land has increased for habitation sites, industrial complexes and new towns on the west seaside of Korea. The planting models have to consider endurance for bad environmental conditions in order to make a role to protect the urban space against the extreme seaside environment. The dominant species, relative impotance value, individuals and species number were analysed in natural forests that were exposed to extreme seaside conditions in Deokjeok island and Younghung island, Incheon. The native species such as Pinus thunbergii and Pinus densiflora, which survive on the seaside, were mainly recommended because the coastal reclaimed land had extreme environmental conditions. Stable vegetation structures could be made by multi-layer planing by using these species. A diverse vegetation community could be made according to these planting models. The maritime forests made by these planting models might be more effective for environmental adaptation and a windbreak forest than alone tree, and the young trees below 3m height could easily adapt to these conditions.

농작물 질병분류를 위한 전이학습에 사용되는 기초 합성곱신경망 모델간 성능 비교 (Performance Comparison of Base CNN Models in Transfer Learning for Crop Diseases Classification)

  • 윤협상;정석봉
    • 산업경영시스템학회지
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    • 제44권3호
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    • pp.33-38
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    • 2021
  • Recently, transfer learning techniques with a base convolutional neural network (CNN) model have widely gained acceptance in early detection and classification of crop diseases to increase agricultural productivity with reducing disease spread. The transfer learning techniques based classifiers generally achieve over 90% of classification accuracy for crop diseases using dataset of crop leaf images (e.g., PlantVillage dataset), but they have ability to classify only the pre-trained diseases. This paper provides with an evaluation scheme on selecting an effective base CNN model for crop disease transfer learning with regard to the accuracy of trained target crops as well as of untrained target crops. First, we present transfer learning models called CDC (crop disease classification) architecture including widely used base (pre-trained) CNN models. We evaluate each performance of seven base CNN models for four untrained crops. The results of performance evaluation show that the DenseNet201 is one of the best base CNN models.

Effects of micromechanical models on the dynamics of functionally graded nanoplate

  • Tao Hai;A. Yvaz;Mujahid Ali;Stanislav Strashnov;Mohamed Hechmi El Ouni;Mohammad Alkhedher;Arameh Eyvazian
    • Steel and Composite Structures
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    • 제48권2호
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    • pp.191-206
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    • 2023
  • The present research investigates how micromechanical models affect the behavior of Functionally Graded (FG) plates under different boundary conditions. The study employs diverse micromechanical models to assess the effective material properties of a two-phase particle composite featuring a volume fraction of particles that continuously varies throughout the thickness of the plate. Specifically, the research examines the vibrational response of the plate on a Winkler-Pasternak elastic foundation, considering different boundary conditions. To achieve this, the governing differential equations and boundary conditions are derived using Hamilton's principle, which is based on a four-variable shear deformation refined plate theory. Additionally, the Galerkin method is utilized to compute the plate's natural frequencies. The study explores how the plate's natural frequencies are influenced by various micromechanical models, such as Voigt, Reuss, Hashin-Shtrikman bounds, and Tamura, as well as factors such as boundary conditions, elastic foundation parameters, length-to-thickness ratio, and aspect ratio. The research results can provide valuable insights for future analyses of FG plates with different boundaries, utilizing different micromechanical models.

해상풍력발전의 HSE 관리를 위한 모델기반 HSE 위험성 평가 모듈 개발 및 평가 (Development and evaluation of a model-based HSE risk assessment module for HSE management in offshore wind power)

  • 김성래;남건우;이태경;강대영;김준영
    • 시스템엔지니어링학술지
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    • 제19권2호
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    • pp.74-91
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    • 2023
  • This study provides an in-depth comparison and analysis of various risk assessment models widely used in modern industries, and proposes the most suitable model for risk assessment of offshore wind power in Korea. The assessment models were selected by considering various factors such as the purpose of risk assessment, stakeholder requirements, and characteristics of offshore wind power. We also emphasized the importance of using different risk assessment models in combination in situations of high uncertainty. To systematize the combination of risk assessment models, we used systems engineering which is effective to develop a new system. Systems engineering was used to define the complete, traceable functions from site requirements, and model-based systems engineering was used to manage the design information from requirements to detailed functions in a single model. The developed risk assessment module provide automatic conversion between risk assessment models to enable risk assessment suitable for offshore wind power. The functionality and usability of the offshore wind risk assessment module were verified by the evaluation of three wind power experts.

구조모델을 이용한 암석의 유효열전도도 분석 (Analyzing Effective Thermal Conductivity of Rocks Using Structural Models)

  • 차장환;구민호;김영석;이영민
    • 자원환경지질
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    • 제44권2호
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    • pp.171-180
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    • 2011
  • 화강암, 사암, 편마암으로 구성된 21개 암석시료를 대상으로 열전도도를 측정하고, XRD 정량분석을 통해 구성광물의 조성을 파악하였으며, 구조모델 이용하여 석영 함량 및 광물입자의 크기가 암석의 유효열전도도에 미치는 영향을 분석하였다. 측정된 열전도도는 석영 함량과 높은 상관성을 보여 ($R^2=0.75$), 석영 함량으로부터 열전도도를 추정할 수 있는 선형회귀모형을 제시하였다. 화강암 및 변성암 일부 시료의 경우 유사한 석영 함량에도 불구하고 열전도도가 크게 다른 값을 보였는데, 이는 주로 광물업자의 크기 변화와 관련이 있는 것으로 나타났다. 구조모델을 통한 분석 결과 입자의 크기가 작은 경우 열전도도는 scries와 EMT모델의 중간 영역에 해당하는 값을 보이며, 입자가 커지면서 EMT모델, ME모델을 거쳐 Parallel모델에 근접하게 변화하였다. 이러한 열전달 구조모델의 변화는 입자의 크기에 따른 열전도도 변화가 3 mm 두께의 원반시편을 이용하는 실험 규모와 관련이 있음을 시사한다. 즉, 얇은 원반 시료를 이용하여 암석의 열전도도를 측정할 경우 규모효과에 의하여 실제 지반의 값보다 과대평가될 가능성이 높으며, 특히 광물 입자의 크기가 클수록 이러한 오차는 더 커질 것으로 예상된다. 따라서 지열과 관련된 다양한 해석 모델에서 실험실 측정값을 실제 현장규모에서의 대표값으로 사용할 경우 모델의 예측 신뢰도에 영향을 줄 수 있는 요인으로 작용할 수 있다.

좌골신경통 백서모델에서 침치료의 효과: 체계적 문헌고찰 및 메타분석 (Effect of Acupuncture on Sciatica in Rat Models: Systematic Review and Meta-analysis)

  • 윤예지;김수전;조재흥;김고운;송미연
    • 한방재활의학과학회지
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    • 제30권1호
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    • pp.79-93
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    • 2020
  • Objectives While sciatic neuropathy is one of the common symptoms which have the lifetime incidence of 13~40%, still there is no consensus about the standardized and the most effective conservative treatment. In addition, the importance of systematic review and meta-analysis of preclinical are growing as they could suggest possible effective treatment strategy for future studies. Therefore, we conducted systematic review and meta-analysis to estimate analgesic effect of acupuncture on sciatica in rat models. Methods Systematic search was conducted for all controlled comparative preclinical trials which assessed analgesic effect of acupuncture in sciatica rat models. Database of PubMed, EMBASE, Web of Science, CNKI and 6 Korean databases were used. The primary outcome was pain, which is evaluated by stimulus behavior tests in rat models. We assessed the methodological quality with Systematic Review Centre for Laboratory Animal Experimentation's risk of bias tool. RevMan 5.3 was used for meta-analysis and subgroup analysis was conducted according to treatment site, acupuncture point, treatment period and frequency used in electroacupuncture. Results 14 studies were finally included following our inclusion criteria. The data from meta-analysis indicated that the acupuncture significantly improved the result values of behavior tests for pain evaluation, compared to no-treatment control group in animal models (standardized mean difference=4.43, 95% confidence interval 3.16 to 5.69, Z=6.84, p<0.00001; χ2=68.02, p<0.00001; I2=82%). The results of subgroup analysis indicate that acupuncture treatment of unilateral site, distal acupoints, longer treatment period and applying 2/100 Hz frequency in electroacupuncture could be more effective. Conclusions Systematic review and meta-analysis of animal studies are getting important for the future clinical studies and the improvement of heatlh care. Therefore the results of the study would provide evidence and better design for the forthcoming studies.

장기요양대상노인의 비공식적·공식적 자원연계 유형에 따른 서비스 만족도 연구 (A Study on Satisfaction of Service by the Models of Informal-formal Resources Linkages for Long-term Care Elder)

  • 김금열
    • 한국노년학
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    • 제30권4호
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    • pp.1027-1044
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    • 2010
  • 본 연구는 노인장기요양보험제도의 도입으로 공식적 보호가 확대되고 있지만 여전히 장기요양대상노인의 케어에는 비공식적 보호 욕구가 줄어들지 않고 있는 현상에 대해 효과적인 장기요양서비스 제공체계 고찰의 필요성에서 시작되었다. 따라서 본 연구의 목적은 장기요양대상노인의 비공식적·공식적 자원연계 유형을 도출하고 각 유형에 따른 서비스 만족도의 차이를 살펴봄으로서 효과적인 장기요양서비스 제공 모델을 발견하는 것이다. 이를 위해서 비공식적·공식적 자원연계 유형은 장기요양대상노인에게 15가지 케어관련과업을 제공하는 비공식적 보호제공자와 공식적 서비스제공자의 서비스 제공정도를 군집분석으로 구분하였고 각 유형에 따른 서비스 만족도의 차이는 다중회귀분석으로 분석하였다. 연구결과 비공식적·공식적 자원연계 유형은 가족수발 중심형, 상호 보완형, 과업 분리형, 공식적 수발 중심형으로 구분되었고 서비스 만족도가 가장 높게 나타난 유형은 상호 보완형 이었으며 이를 바탕으로 다음과 같은 점을 논의하였다. 첫째, 비공식적 보호와 공식적 서비스가 상호 보완적으로 제공되기 위해서는 공식적 서비스 제공체계에 비공식적 보호제공자의 역할을 결합시키는 노력이 필요하다. 둘째, 15가지 케어관련과업 중 개인적 및 일상생활지원 과업과 건강보호 과업은 서비스 제공자가 분리되어 있어 의료 및 장기요양서비스의 연계를 위한 통합적 케어 방안이 필요하다. 셋째, 공식적 서비스 제공자가 거의 모든 케어를 제공하는 공식적 수발 중심형은 상대적으로 서비스 만족도가 낮게 나타나 이에 대한 대책이 필요하다. 이상의 결과를 바탕으로 본 연구는 장기요양서비스의 효과성 향상을 위해서는 서비스의 양(量)과 질(質)적 차원에서 비공식적·공식적 자원연계 유형을 파악하고 서비스 제공 방안을 모색할 필요가 있다는 제언을 하였다.

Soil arching analysis in embankments on soft clays reinforced by stone columns

  • Fattah, Mohammed Y.;Zabar, Bushra S.;Hassan, Hanan A.
    • Structural Engineering and Mechanics
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    • 제56권4호
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    • pp.507-534
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    • 2015
  • The present work investigates the behavior of the embankment models resting on soft soil reinforced with ordinary and stone columns encased with geogrid. Model tests were performed with different spacing distances between stone columns and two lengths to diameter ratios (L/d) of the stone columns, in addition to different embankment heights. A total number of 42 model tests were carried out on a soil with undrianed shear strength $${\sim_\sim}10kPa$$. The models consist of stone columns embankment at s/d equal to 2.5, 3 and 4 with L/d ratio equal 5 and 8. Three embankment heights; 200 mm, 250 mm and 300 mm were tested for both tests of ordinary (OSC) and geogrid encased stone columns (ESC). Three earth pressure cells were used to measure directly the vertical effective stress on column at the top of the middle stone column under the center line of embankment and on the edge stone column for all models while the third cell was placed at the base of embankment between two columns to measure the vertical effective stress in soft soil directly. The performance of stone columns embankments relies upon the ability of the granular embankment material to arch over the 'gaps' between the stone columns spacing. The results showed that the ratio of the embankment height to the clear spacing between columns (h/s-d) is a key parameter. It is found that (h/s-d)<1.2 and 1.4 for OSC and ESC, respectively; (h is the embankment height, s is the spacing between columns and d is the diameter of stone columns), no effect of arching is pronounced, the settlement at the surface of the embankment is very large, and the stress acting on the subsoil is virtually unmodified from the nominal overburden stress. When $(h/s-d){\geq}2.2$ for OSC and ESC respectively, full arching will occur and minimum stress on subsoil between stone columns will act, so the range of critical embankment height will be 1.2 (h/sd) to 2.2 (h/s-d) for both OSC and ESC models.

Comparing Role of Two Chemotherapy Regimens, CMF and Anthracycline-Based, on Breast Cancer Survival in the Eastern Mediterranean Region and Asia by Multivariate Mixed Effects Models: a Meta-Analysis

  • Ghanbari, Saeed;Ayatollahi, Seyyed Mohammad Taghi;Zare, Najaf
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권14호
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    • pp.5655-5661
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    • 2015
  • Purpose: To assess the role of two adjuvant chemotherapy regimens, anthracycline-based and CMF on disease free survival and overall survival breast cancer patients by meta-analysis approach in Eastern Mediterranean and Asian countries to determine which is more effective and evaluate the appropriateness and efficiency of two different proposed statistical models. Materials and Methods: Survival curves were digitized and the survival proportions and times were extracted and modeled to appropriate covariates by two multivariate mixed effects models. Studies which reported disease free survival and overall survival curves for anthracycline-based or CMF as adjuvant chemotherapy that were published in English in the Eastern Mediterranean region and Asia were included in this systematic review. The two transformations of survival probabilities (Ln (-Ln(S)) and Ln(S/ (1-S))) as dependent variables were modeled by a multivariate mixed model to same covariates in order to have precise estimations with high power and appropriate interpretation of covariate effects. The analysis was carried out with SAS Proc MIXED and STATA software. Results: A total of 32 studies from the published literature were analysed, covering 4,092 patients who received anthracycline-based and 2,501 treated with CMF for the disease free survival and in order to analyze the overall survival, 13 studies reported the overall survival curves in which 2,050 cases were treated with anthracycline-based and 1,282 with CMF regimens. Conclusions: The findings illustrated that the model with dependent variable Ln (-Ln(S)) had more precise estimations of the covariate effects and showed significant difference between the effects of two adjuvant chemotherapy regimens. Anthracycline-based treatment gave better disease free survival and overall survival. As an IPD meta-analysis in the Italy the results of Angelo et al in 2011 also confirmed that anthracycline-based regimens were more effective for survival of breast cancer patients. The findings of Zare et al 2012 on disease free survival curves in Asia also provided similar evidence.

Estimates of Genetic Parameters and Genetic Trends for Production Traits of Inner Mongolian White Cashmere Goat

  • Bai, Junyan;Zhang, Qin;Li, Jinquan;Dao, Er-Ji;Jia, Xiaoping
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권1호
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    • pp.13-18
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    • 2006
  • Two different animal models, which differ in whether or not taking maternal genetic effect into account, for estimating genetic parameters of cashmere weight, live body weight, cashmere thickness, staple length, fiber diameter, and fiber length in Inner Mongolia White Cashmere Goat were compared via likelihood ratio test. The results indicate that maternal genetic effect has significant influence on live body weight and cashmere thickness, but no significant influence on the other traits. Using models suitable for each trait, both genetic parameters and trends were analyzed with the MTDFREML program. Heritability estimates from single trait models for cashmere weight, live body weight, cashmere thickness, staple length, fiber diameter and fiber length were found to be 0.30, 0.07, 0.21, 0.29, 0.28 and 0.21, respectively. Genetic correlation estimates from two-trait models between live body weight and all other traits (-0.06~0.07) was negligible, as were those between fiber diameter and all other traits (-0.01~0.03) except cashmere thickness (0.19). Cashmere weight and staple length had moderate to low genetic correlations with other traits (-0.24~0.39 and -0.24~0.34, respectively) except for live body weight and fiber diameter. Cashmere thickness had a strong genetic correlation with fiber length (0.81), and low genetic correlation with other traits (0.19~0.34) except live body weight. Genetic trend analysis suggests that selection for cashmere weight was very effective, which has led to the slow genetic progress of cashmere thickness and fiber length due to their genetic correlations with cashmere weight. The selection for live body weight was not effective, which was consistent with its low inheritability.