• Journal of the korean veterinary medical association
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• v.47 no.3
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• pp.272-276
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• 2011

최근의 연구에 의하면 자연계 또는 인류가 합성한 수많은 화합물질들이 내분비계를 교란하여 야생 도물, 조류, 어류 및 인체에 부작용을 일으킨다고 보고되고 있다. 이들 내분비계를 교란시키는 물질들을 과학자들은 "내분비계 장애물질 (endocrine disruptors, 언론에서는 환경호르몬으로 소개됨)"이라고 부른다. 이들 내분비계 장애물질은 일상 생활에서 우리 주변에서 흔히 볼 수 있는 것으로서 플라스틱, 캔, 세제, 내연제, 음식, 완구, 화장품, 살충제, 약품 등에 광범위하게 분포되어 있다. 우리는 음식물, 음료수, 약품, 화장품 등에 포함된 내분비계장애물질을 구강 또는 피부로 이들 물질을 섭취하고 있다. 아직까지 이들 화합물질에 대한 정확한 부작용이 규명되지 않고 있는 문제점이 있음에도 불구하고 동물과 사람은 다양한 이들 화합물에 노출되고 있다.

• Journal of Gifted/Talented Education
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• v.17 no.1
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• pp.51-76
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• 2007

The study was conducted to analyze the extent of students' creativity through the use of scaffolding composed of different kinds of experience in making insights on problem solving and to investigate the function of a new scaffolding type which is not used in accomplishing a phase of activity but in having an insight. The students' achievements in problem solving given the scaffolding for on-site experience were compared with those given the scaffolding using stories. Also, the extent of creativity of the first- and sixth- grade students using the two types of scaffolding were investigated as they carried out picture completion task from TTCT. The results of the study showed that the control groups not given the scaffolding in post-test did not advance in creativity but experimental groups given the scaffolding showed improvement in some subordinate elements after scaffolding. Moreover, scaffolding using stories were more effective in enhancing the students' creativity than the scaffolding using on-site experience.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2001.02a
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• pp.12-13
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• 2001

과학자들 사이에서만 논의되어 왔던 내분비계 장애물질 문제가 일반인들의 관심을 얻게 된 것은 T.Colborn, D.Dumanoski와 J.P.Myers가 과학논문을 근거로 집필한 '도둑맞은 미래(Our Stolen Future)'의 발간이 계기가 되었다 (1996년 1월). 그 후 컵라면 용기에서의 styrene dimers & trimers 검출 논란이 제기되면서 일본 및 우리나라에서도 관심을 갖게 되었는데, 이제 내분비계 장애물질 문제는 단순한 과학적 문제가 아니라 중요한 사회적, 환경적 문제로 인식되고 있으며 지구 온난화, 오존층 파괴와 더불어 지구 3대 환경 문제 중 하나로까지 거론되고 있다. 내분비계 장애물질 문제는 아직까지 명확히 규명되지 않은 상태로 인체에 미치는 영향을 밝히기까지는 장기간의 집중 연구가 필요하다. 여기서는 내분비계 장애작용 검색 및 시험법 확립을 위한 현 시점에서의 국제적 노력에 대하여 미국 EPA 및 OECD를 중심으로 알아보고 OECD 내분비계 장애물질 시험법 확립을 위한 국제협력연구의 일부 실험결과를 발표하고자 한다.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2022.10a
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• pp.231-232
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• 2022

건설 현장이나 일반 제조업 현장은 작업자의 고소 위치에서의 작업시, 필요한 특정 장소로의 접근을 위한 임시 구조물을 설치하는데 이를 가설비계라고 한다. 이러한 가설비계는 작업자의 안전 통행과 작업을 위한 받침대 역할, 장비나 공구, 자재를 임시 적치하기 위한 장소로 활용되는데 일반 건축물과 중후장대한 조선소 블록 제작등에 필수적으로 사용된다. 하지만 가설설비라는 특성으로 비계와 관련된 연구가 부진하고 사업적으로 참여하는 사업주 또한 진출을 가볍게 생각하고 있으며 해당 공사에 임하는 작업자의 산업으로의 진입문턱도 낮은 등으로 시공 품질이 떨어질 우려가 매우 높다. 또한 설치후에는 품질검사가 어려워 작업자의 숙련도나 진정성 등에 의한 주관적 작업 결과물이 설치된 시설물을 사용하는 주변 작업자에게는 불안전 요인이 되기도 한다. 이에 작업자의 숙련도나 주관적 판단에 의한 가설 구조물 설치를 회피하여 안전성을 높이기 위한 방안이 연구되어 왔는데 이것이 시스템비계이다. 이러한 시스템비계에 대한 사용성을 확대하기 위해 국토교통부와 고용노동부등의 정부기관에서는 여러 가지 제약과 동시에 장려정책을 제시하고 있으나 공적 발주나 일부 대기업그룹 외의 중소 현장에는 그 확산 속도가 높지않은 편이다.

• Korean Journal of Environmental Biology
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• v.33 no.4
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• pp.361-374
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• 2015

Endocirne disruptors (EDs) can cause fertility decrease, developmental disorder, and even cancer in animals. Until 90's, EDs were used in various synthetic products including paints, coatings, detergents, plastics, and plasticizers. Currently, in several countries, the production, trade and use of EDs or EDs-suspected chemicals have been regulated while activity to screen the alternatives for EDs including bisphenol-A, phthalate and nonylphenol is active. Although various toxicity test method was developed and applied for screening of alternatives, however, the safety of alternatives has been not fully demonstrated. Some alternatives have high structural similarity with existing EDs, raising the possible risk of endocrine disruption by alternatives. In an effort to develop the safe alternatives, we reviewed the effects of EDs such as bisphenol-A, phthalates, nonylphenol and their substituents. In addition, in-silico analysis for endocrine disrupting activities of some alternatives was presented.

• Journal of Educational Research in Mathematics
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• v.15 no.1
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• pp.57-74
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• 2005

The aim of this study is to reflect Vygotsky's theory of Zone of Proximal Development and other scholars' scaffolding theories emboding the theory and to examine the effects of mathematics instruction by scaffolding. The subjects of this study consist of 8 fifth graders attending S elementary school which is located in San-Chung county. The teaching-learning processes were videotaped and analysed according to scaffolding components. The results between pretest and posttest regarding to fraction were compared and the responses of students to a questionnaire on the mathematical attitude before and after the teaching experiment. It concludes that mathematics instruction by scaffolding was effective to improve students' mathematical learning ability and positive mathematical attitude.

• Journal of Life Science
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• v.32 no.1
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• pp.70-77
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• 2022

Endocrine disrupting chemicals (EDCs) have been attracting significant attention in modern society, owing to the increased incidence rate of various diseases along with population growth. EDCs are found in many commercial products, including some plastic bottles and containers, detergents, liners of metal food cans, flame retardants, food, toys, cosmetics, and pesticides. EDCs have a hormonal effect on the human body, which disrupts the endocrine system, notably affecting sexual differentiation and normal reproduction, and can trigger cancer as well. Recently, the association between neurological diseases and EDCs has become a hot topic of research in the field of neuroscience. Considering that EDCs negatively affect not only neuronal proliferation and neurotransmission but also the formation of the neuronal networks, EDCs may induce neurodevelopmental disorders, such as autism spectrum disorders and attention-deficit/hyperactivity disorder as well as neurodegenerative diseases, including Parkinson's disease and Alzheimer's disease. In light of these potentially deleterious outcomes, important efforts have been underway to minimize the exposure to EDCs through appropriate regulations and policies around the world, but chemicals that have not yet been associated with endocrine disrupting properties are still in wide use. Therefore, more epidemiological investigations and research are needed to fully understand the effects of EDCs on the nervous system.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.7
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• pp.679-683
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• 2016

Boilers of large-sized coal-fired power plants are being operated under very poor conditions such as continuous operation or repeating of start-up and shutdown for a stable supply of electricity. Thus periodic inspection and maintenance are required to ensure reliability of operation. The loads of existing scaffolding systems for the maintenance of boilers are concentrated in the lower parts structurally, which may cause a serial collapse of the overall scaffolding system when there are problems in some members. Therefore, in this study, a safe furnace scaffolding system is developed by dispersing the loads in the upper part, as well as minimizing the hazards of serial collapsing. In addition, for cases where the direct installation of furnace scaffolding is challenging owing to the structure of the boiler tube, a lifting system for the installation of furnace scaffolding is developed so that furnace scaffolding can be supported to secure the integrity of the power generating facility.

• The Korean Journal of Applied Statistics
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• v.12 no.1
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• pp.1-15
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• 1999

수산물 비계통 생산량 조사는 수산물 생산량 조사 중 어가부분에서 비계통 출하된 양에 대한 표본조사이다. 본연구는 1995년 어업 총조사 자료에 근거하여 새로운 표본 설계를 제안하는 것을 목적으로 한다. 표본은 층화 2단 집락 추출방식에 의해 추출되었으며 층화변수로는 어업조사구 내의 일반어류 어가 비율을 사용하였다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.25-26
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• 2021

System scaffolding and shoring are temporary structures in which vertical members, horizontal members, bracing members and trusses are assembled and installed. In order to ensure quality and safety, the quality test shall be carried out in accordance with the Guidelines for Quality Management of Construction Works (MOLIT Notice No. 2020-750). The quality test method (national standard) for Components for tied post system scaffolding and shoring is based on the Korean standards (KS F 8021) and the Safety certification standards (MOEL Notice No. 2021-22). However, the two standards differ in some aspects such as performance standards and etc, so cause confusion when applying them on-site. In addition, the standard for truss are applied only to trusses for shoring and cannot be applied to trusses for scaffolding. Therefore, this study aims to unify the two national standards and establish realistic standards.