• 제목/요약/키워드: Relative depth evaluation

검색결과 76건 처리시간 0.029초

콘크리트의 형상비 및 온도변화에 따른 부착강도 특성평가 (Evaluation of Bond Strength Properties with Changing the Aspect Ratio and Temperature of Concrete)

  • 김현석;정원경;오한진;박준영;김형배
    • 한국도로학회논문집
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    • 제20권3호
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    • pp.19-26
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    • 2018
  • PURPOSES : The main purpose of this study is suggest of field bond strength evaluation method for more objective evaluation method through Evaluation of Bond Strength Properties with changing aspect ratio and temperature. METHODS : The evaluation is laboratory bond strength test. Using the core machine, the pull-off test method ; the bond strength test of interface layer the universal testing machine. RESULTS : As a result of the laboratory bond strength evaluation, it was verified that the bond strength by aspect ratio decreases linearly with increasing aspect ratio and the bond strength properties by temperature change existed at high and low temperature condition relative to odinary temperature condition. CONCLUSIONS : According to the results of laboratory bond strength evaluation, the field bond strength evaluation results suggest applying the proposed correction factor (0.8, 1.0, 1.4, 1.9) according to aspect ratio(0.5, 0.1, 1.5, 2.0), For more objective evaluation of the bond strength, it is analyzed that the evaluation value is within $6{\sim}32^{\circ}C$ and the result can be obtained within 5% of the coefficient of variation.

Evaluation of Environmental Factors to Determine the Distribution of Functional Feeding Groups of Benthic Macroinvertebrates Using an Artificial Neural Network

  • Park, Young-Seuk;Lek, Sovan;Chon, Tae-Soo;Verdonschot, Piet F.M.
    • Journal of Ecology and Environment
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    • 제31권3호
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    • pp.233-241
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    • 2008
  • Functional feeding groups (FFGs) of benthic macroinvertebrates are guilds of invertebrate taxa that obtain food in similar ways, regardless of their taxonomic affinities. They can represent a heterogeneous assemblage of benthic fauna and may indicate disturbances of their habitats. The proportion of different groups can change in response to disturbances that affect the food base of the system, thereby offering a means of assessing disruption of ecosystem functioning. In this study, we used benthic macroinvertebrate communities collected at 650 sites of 23 different water types in the province of Overijssel, The Netherlands. Physical and chemical environmental factors were measured at each sampling site. Each taxon was assigned to its corresponding FFG based on its food resources. A multilayer perceptron (MLP) using a backpropagation algorithm, a supervised artificial neural network, was applied to evaluate the influence of environmental variables to the FFGs of benthic macroinvertebrates through a sensitivity analysis. In the evaluation of input variables, the sensitivity analysis with partial derivatives demonstrates the relative importance of influential environmental variables on the FFG, showing that different variables influence the FFG in various ways. Collector-filterers and shredders were mainly influenced by $Ca^{2+}$ and width of the streams, and scrapers were influenced mostly with $Ca^{2+}$ and depth, and predators were by depth and pH. $Ca^{2+}$ and depth displayed relatively high influence on all four FFGs, while some variables such as pH, %gravel, %silt, and %bank affected specific groups. This approach can help to characterize community structure and to ecologically assess target ecosystems.

촉진중성화 조건에 따른 콘크리트의 중성화 특성에 관한 실험적 연구 (An Experimental Study on the Carbonation Properties of Concrete According to Accelerating Carbonation Conditions)

  • 문형재;이의배;송민섭;주지현;조봉석;김무한
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2004년도 학술.기술논문발표회
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    • pp.41-44
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    • 2004
  • Recently, in the case of domestic, for all that the deterioration environment about the carbonation of reinforced concrete structures is accelerated, systematic diagnosis and researches are not completed. And the selection techniques of repair material and method used under the situation that the indicator and the performance evaluation method are nor established are dependant on existing experience. Therefore, the purpose of this study is intend to present fundamental data for the reasonable selection of repair material and method. durability design and longevity on the deteriorated reinforced concrete structures, through computing the carbonation depth and velocity coefficient by accelerating carbonation test under various accelerating conditions and investigating the application of carbonation evaluation method. The results of this study are as follow; The resistances to carbonation are increased when the W/C ratio if lower and the treatment of surface coating is executed. And the carbonation depth and velocity coefficient according to accelerating carbonation test conditions are increased when the conditions of temperature, relative humidity and $CO_2$density are higher individually.

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A Study on Computing Method of the Individual Scholastic Evaluation in the Comparative School Record

  • Chung, Yeon-soo
    • Communications for Statistical Applications and Methods
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    • 제6권2호
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    • pp.635-644
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    • 1999
  • This study aims at solving the problem in the application method of the comparative school record which is currently being discussed in depth among colleges. The application method of Kay O. Lee and Yeon Soo Cung(1997) which was appied in the 1999 Korean air force Academy Admission Process was found to be problematic in the following respects. First the setting of the standard which divides all the high schools in kora into five groups relative to their scholastic level is somewhat vague and subjective secondly the difference among those levels which resulted from the five grouping could greatly influence on the admission of the applicants and thirdly there is no standard in choosing those few promising individuals with high scholastic aptitude test results from the low level groups such as level four and five,. Therefore this study suggests and introduces a nationwide individual scholastic evaluation that would complement the limits and problems in the application method of the comparative school record.

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깊이맵 업샘플링 방법의 객관적 성능 측정과 3D 시각적 피로도의 관계 분석 (Analysis of Relationship between Objective Performance Measurement and 3D Visual Discomfort in Depth Map Upsampling)

  • 길종인;사이드마흐모드포어;김만배
    • 방송공학회논문지
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    • 제19권1호
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    • pp.31-43
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    • 2014
  • 깊이맵은 3D 입체영상의 생성을 위해 중요한 요소이다. 하지만 깊이 카메라를 이용하여 획득한 깊이맵들은 낮은 해상도를 갖는 단점이 있기 때문에 이를 고해상도로 변환하는 연구들이 활발하게 진행되고 있다. 이러한 연구들은 일반적으로 PSNR, Sharpness Degree, Blur Metric 등과 같은 객관적인 평가방법으로 성능을 검증해왔다. 이러한 평가방법 이외에 DIBR로 가상시점(virtual view)을 생성하여 주관적으로 평가하는 연구도 있으나, 입체영상을 생성하여 깊이맵 업샘플링의 성능을 분석하는 것은 많지 않다. 본 논문에서는 다양한 깊이맵 업샘플링 방법들을 이용하여 생성된 입체영상의 주관적 평가와 업샘플링 방법의 객관적 평가 결과의 상관관계 및 선형회귀법을 이용하여 관련성을 분석한다. 실험결과에서는 에지 PSNR이 시각적 피로도와의 상관관계가 가장 높고, Blur Metric은 가장 낮다는 것을 보여준다. 또한 선형회귀에서는 최적의 입체영상을 얻을 수 있는 객관적 평가의 가중치를 구하고, 기존 또는 새로운 업샘플링 알고리즘의 3D성능을 예측할 수 있는 공식을 보여준다.

FWD 방향을 고려한 콘크리트 포장 하부 상태 평가 (Evaluation of State of Concrete Pavement Sublayers Considering Direction of FWD)

  • 이재훈;이재훈;손덕수;유주호;정진훈
    • 한국도로학회논문집
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    • 제16권6호
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    • pp.69-78
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    • 2014
  • PURPOSES : The purpose of this paper is showing that the state of pavement sublayers can be evaluated differently according to direction of FWD. METHODS : The concrete pavement slabs above subgrade without anything, subgrade with cavity, and box culvert were modeled by finite element method(FEM). The modeled pavements were analyzed by changing the direction of falling weight deflectometer(FWD). The deflection results obtained from FEM were used to calculate radius of relative stiffness and composite modulus of subgrade reaction using AREA method. Then, the analyzed results were compared to the results of the test performed at the Korea Expressway Corporation(KEC) test road. RESULTS : The composite modulus of subgrade reaction increased with subgrade elastic modulus, while radius of relative stiffness decreased. The pavement sections of pure earth showed the consistent results regardless of FWD direction. In case there was cavity, the radius of relative stiffness was larger and composite modulus of subgrade reaction was smaller when FWD was leaving the cavity than when approaching the cavity. This pattern became clear when the cavity got larger. In case of the section with box culvert, the pattern was opposite to the case of cavity. When the soil cover depth increased, the effect of box culvert got smaller. When the load was applied far from the cavity and box culvert, the effect was also declined. The test performed at the KEC test road showed identical results to those of finite element analysis. CONCLUSIONS : The direction of FWD should be considered in evaluation of the state of pavement sublayers because it can be evaluated differently even under identical condition.

입출력 정보 조건에 따른 코드 설계 평가 방법 분석 (Analysis of Code Design Evaluation Methods According to Input/Output Information Conditions)

  • 허경
    • 실천공학교육논문지
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    • 제16권3_spc호
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    • pp.259-265
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    • 2024
  • 대학 학부생들의 SW융합 역량을 향상하기 위해서는, 관련 강좌의 개발과 함께 학부생들의 코드 설계 역량을 평가하는 방법이 연구되어야 한다. 기존 연구에서는 코드 결과물에 대해 정성적인 평가방법과 정량적인 상대평가방법이 있었으며, 정량적인 상대평가방법에서는 문제분해깊이 수, 함수재사용 회수와 함수 개수를 측정하여 평가하였다. 본 연구에서는 기존 연구에서 제시되지 않은 평가방법으로서, 코드 설계 시 입력과 출력 정보종류의 수를 제시하는 문제를 이용한 평가방법을 제안하였다. 본 논문에서 제안한 평가 문제들은 입력 정보 종류의 수와 출력 정보 종류의 수를 3개까지 적용하였다. 이를 통해 5가지 코드설계 평가문제를 제시하고 코드설계 점수를 정량적으로 산출하는 방법을 제안하였다. 제안한 평가방법을 적용한 강좌를 통해 100명 학생 응답자들의 코드들을 수집하고 분석하였다. 결과 분석을 통해, 문제분해깊이 수는 입력 정보의 종류 개수에 비례하고, 함수 재사용 회수는 출력 정보의 종류 개수에 비례하며, 함수 개수는 입력과 출력 정보의 종류 총개수에 비례하는 상관성을 나타내었다. 마지막으로 100명 응답자의 평가 점수 분포를 분석하여, 5가지 입출력 정보 조건 평가문제에 따른 코드설계 평가 방법이 유효함을 설명하였다.

Efficacy Evaluation of Anti-wrinkle Products in Japan

  • Masaki Hitoshi
    • 대한화장품학회지
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    • 제29권2호
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    • pp.67-77
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    • 2003
  • Two categories of cosmetic products, cosmetics and quasi-drugs, have been established by the Ministry of Health, Labor and Welfare (MHLW) in Japan. Japanese pharmaceutical law has defined that products categorized as cosmetics do not exhibit any effects on human skin. In fact, cosmetic products are not permitted to claim any efficacy. On the other hand, products in the quasi-drug category can claim several efficacies such as anti-inflammatory effects, whitening/lightning effects, hair growth effects and so on. Unfortunately, the Japanese MHLW has not yet approved the efficacy of anti-aging/anti-wrinkle effects as a claim point. However, the population is aging, and the demand for anti-aging/anti-wrinkle products is increasing year by year. Japanese cosmetic companies have proposed to the MHLW that anti-aging/anti-wrinkle agents be approved as a claim concept of a quasi-drug. However, unified evaluation methods for anti-aging/anti-wrinkle effects have not been established. Currently, each company evaluates the efficacy of products/materials using their own original methods. Thus, to request approval of the MHLW, the establishment of a unified evaluation method is needed. Consequently, the Japan Cosmetic Industry Association (JCIA) has established a task force to develop guidelines for evaluating anti-wrinkle effects in 1998. In conclusion, the JCIA would like to adopt visual and image analysis scales to evaluate the anti-wrinkle effects objectively. Generally, wrinkles are roughly classified into three groups as fine wrinkles, linear deep wrinkles and crow's feet. However, academic societies of dermatology or cosmetics have not yet established a definition of wrinkles in Japan. Thus, in advance of setting up an evaluation method, the definition of wrinkles f3r evaluation must be decided. Wrinkles are defined by the task force of the JCIA as follows; furrows that people can recognize visually and that appear on the forehead, the corners of the eyes and the backs of the neck with aging. In addition, furrows are emphasized by exposure to solar light and by dry conditions. Visual evaluation is the most sensitive method and can be applied to most types of wrinkles. However, visual evaluation is hard to express digitally as results. Besides, in the case of image analysis, comparisons of data obtained from distinct examinations can not be done, because data from image analysis are relative values. Thus, to enhance the reliability of the evaluations, the adoption of an objective scale was required. The principle of the evaluation method is to analyze images taken from silicone replicas of wrinkle areas using several parameters, such as the proportion of the wrinkle $area({\%})$, the mean depth of the wrinkles (mm), the mean depth of the deepest wrinkle (m) and the deepest point on the deepest wrinkle. Lights are shown on the skin replica from an orthogonal direction of the main orientation of the wrinkle, and the resulting shadow images are quantified by the image analysis method. To increase the precision of the data or to allow comparisons of independent examinations, a scale with furrows of several depths, 200, 400, 600, 800, and $1000{\mu}m$, is adapted in the evaluation system. I will explain the guidelines established by the JCIA in the presentation.

Evaluation of calcium sulphate barrier to collagen membrane in intrabony defects

  • Budhiraja, Shilpa;Bhavsar, Neeta;Kumar, Santosh;Desai, Khushboo;Duseja, Sareen
    • Journal of Periodontal and Implant Science
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    • 제42권6호
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    • pp.237-242
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    • 2012
  • Purpose: The aim of this study was to clinically and radiographically evaluate and compare treatment of intrabony defects with the use of decalcified freeze-dried bone allograft in combination with a calcium sulphate barrier to collagen membrane. Methods: Twelve patients having chronic periodontal disease aged 20 to 50 years and with a probing depth >6 mm were selected. Classification of patient defects into experimental and control groups was made randomly. In the test group, a calcium sulphate barrier membrane, and in control group, a collagen membrane, was used in conjunction with decalcified freeze-dried bone graft in both sides. Ancillary parameters as well as soft tissue parameters along with radiographs were taken at baseline and after 6 months of surgery. Parameters assessed were plaque index, modified gingival index, probing depth, relative attachment level, and location of the gingival margin. A Student's t-test was done for intragroup and a paired t-test for intergroup analysis. Results: Intragroup analysis revealed statistically significant improvement in all the ancillary parameters and soft tissue parameters with no statistically significant difference in intergroup analysis. Conclusions: The study concluded that a calcium sulphate barrier was comparable to collagen membrane in achieving clinical benefits and hence it can be used as an economical alternative to collagen membrane.

사회기반 시설물의 안전점검 및 정밀안전진단결과 DB 구축방안 연구 (Database Construction Plan of Infrastructure Safety Inspection and In-depth Inspection Results)

  • 유종모;신은철
    • 한국지반신소재학회논문집
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    • 제13권4호
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    • pp.133-141
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    • 2014
  • 본 연구에서는 교량, 터널, 댐, 상수도 등 사회기반 시설물의 안전점검 및 정밀안전진단결과를 DB화하고 업무프로세스를 자동화하기 위해 각 시설물별로 점검진단에 필요한 항목을 표준화해서 분류체계를 마련하였고 사전조사에서부터 현장조사, 시설물평가, 보고서작성에 이르는 전 과정에서 걸쳐 데이터베이스 기반의 자료구조를 정의하고 파일럿시스템을 구현하였다. 또한 점검진단결과 DB가 효과적으로 활용될 수 있도록 개선방안을 제시하고, 시설물정보관리종합시스템 운영규정, 점검진단 세부지침 등 관련 규정/지침에 대한 개선방안을 제시하였다.