탐구는 학교과학에서 지속적으로 강조되어 왔다. 하지만 학교에서 주어지는 문제는 학생들이 일상생활에서 경험하고 부딪치는 문제들과는 여러 면에서 다르다. 본 연구의 목적은 학생들이 문제에 대한 인지도식을 거의 갖고 있지 않을 때, 과제에 대한 태도와 사고력이 문제해결과정, 특히, 문제공간의 형성과 정교화에 어떻게 영향을 미치는지를 알아보는 것이다. 이를 위하여 연구자는 미국의 한 영재센터 여름방학 프로그램 중 4-6학년 영재학생 대상 '레고 로봇 수업'에 참여한 학생들의 문제해결전략을 추적하였다. 결과는 다음과 같다. (1) 과제의 선택과 파악방법, 작동자에 대한 인식의 차이 등 과제에 대한 태도는 서로 다른 문제공간을 형성하게 하였다. (2) 분석적 사고, 융통성, 효율적인 정교화 기술, 기존 인지도식의 적용 등의 사고력의 수준 차이는 문제공간의 정교화 차이와 문제해결의 성공여부로 이어졌다. (3) 초기의 문제공간의 차이는 문제해결전략의 형성 차이를 가져왔지만, 사고력 없이는 효과적인 문제해결전략의 정교화가 이루어지지 못하였다. 마지막으로, 위의 결과를 바탕으로 과학탐구를 증진시킬 몇 가지 사항이 제안되었다.

This study was peformed to investigate effect of feeding experimental mixture containing chitosan, hibiscus extract and L-carnitine on body weight and lipid metabolism in rats. Forty-eight male rats(Charles River CD) of eight weeks old and weighing 336.5±2.3g were raised for five weeks with high fat diet(40% fat as calorie) to induce obesity. After induction of obesity, rats weighing 560.4±5.6g were blocked into four groups according to body weight and raised for eight weeks with diet containing either 0.09%(+1D group), 0.9%(+10D group) or 4.5%(+50D group) of experimental mixture. Aspartate aminotransferase(AST) and alanine aminotransferase(ALT), total protein and albumin were normal levels in plasma. Body weight gain and epididymal fat pad weight were lower in experimental mixture groups than control group However, weights of perirenal fat pad and brown adipose tissue were not significantly different among all groups. There was no significant difference in plasma and hepatic lipid levels among all groups. Liver citrate lyase and camitine acyltransferase activities were not significantly different among all groups, however, citrate lyase activity was tended to be decreased with increasing experimental mixture level in diet. Fecal total lipid and total cholesterol excretions were highest in +50D group, and triglyceride excretion was highest in +1D group. in conclusion, intake of experimental mixture containing chitosan, hibiscus extract and L-camitine was effective in reducing body weight and body fat, and its inhibitory effects might lead to obesity improvement.

공극구조 분석 방법은 ASTM C 457의 리니어트레버스 포인트카운트법이 있으나, 이러한 방법들은 분석하는데 시간과 노력이 너무 많이 소요되어 현재에는 거의 사용되어지지 않고 있다. 근래에는 현미경과 디지털 카메라, 컴퓨터의 프로그램 발달로 화상분석법이 많은 연구자에 의해 연구되고 있다. 본 연구에서는 화상분석법을 통하여 라텍스개질 콘크리트의 공극 구조 특성을 분석하고자 시멘트 종류(보통포틀랜드시멘트, 초속경시멘트)와 라텍스 혼입율(0,15%)에 따라 실험을 수행하였다. 실험결과, 라텍스는 경화 후 콘크리트에서 AE제의 공기연행효과보다 더 우수한 연행공기 량을 갖는 것으로 나타났다. 또한, 화상분석법을 이용할 경우 경화 후 콘크리트 내부 공극 구조에 대한 다양한 정보를 분석할 수 있을 것으로 판단되었다.

Hugo Haring(1882-1952) belonged to that special generation of architects born in the 1880s which became responsible for the establishment of Modern Movement in the 1920s as W. Gropius, Mies Van der Rohe and Le Corbusier, etc. Although he have been overlooked by many historian. He was a key figure of the Modern architecture and as the main theorist for Organic stream in German architecture. He is well-known for his theory of 'Neues Bauen(New Building)', the organic functionalism that is epitomized as the design process from the inside outwards, starting with the life-processes of dwelling. So he argued that the builder must become aware of the life process his building is to serve, and he should not impose a form but try to find the form. These concepts are expressed well in his key-words, the 'Organwerk(organ-work)' and 'Leistungsform(form as achievement)'s. Haring's theory can be found in the short early essay, ""Wege zur Form(approaches to form)"" of 1925. But His concept of 'function' is based on the speciality and individual identity that concerned him from the start, not purely pragmatic aspects. After 1940s his theory moved increasingly in this direction. He defined this as the transition from 'Organwerk' to 'Gesetaltwerk', from mere anatomy to essence, being, personality, life. it suggest that Hugo Haring's idea of Gestalt is a dimension of mystical of symbolic meaning. This paper is about the way in which this theoretical transition can be parallel with contemporary philosophers as E. Cassirer's philosophy of symbolic forms and M. Heidegger's phenomenology. And the key example of this viewpoint is <Gut Garkau>(1921-1926) near Lubeck in Germany, with its 'cowshed' of pear shaped plan devised around the requirements and rituals of farm. This study presents the symbolic conception of Hugo Haring's theory can propose the ability of a symbolic intuition as a view that re-integrate technical thinking with knowledge of other kinds beyond the immediate material.

「시설물의 안전 및 유지관리에 관한 특별법」에 의거하여 정밀안전진단을 실시하는 시설물은 「시설물의 안전 및 유지관리 실시 세부지침」(이하 “세부지침”)에 의거 안정성 평가 및 손상에 대한 상태평가를 수행하고 있다. 그러나 철근노출이 발생하고 손상이 장기화 된 시설물의 철근부식을 고려한 안정성 검토가 미흡한 실정이다. 이에 따라, RC 구조물에 콘크리트 철근노출의 공용년수를 고려하여 구조안전성을 수행하고 상태등급을 산정하였다.

In this study, computer simulation was conducted to evaluate the vulnerability of bridge columns under vehicle impact loading. Firstly, the Preliminary Risk Analysis was conducted to determine if the next step is necessary. In the next step, the Simplified Risk Analysis was conducted to determine the level of risk. According to SRA, if the bridge is confirmed in the category of high risk level, the bridge columns were classified into five types based on the slenderness ratios. Finally, using the five types of bridge columns, the deformation of bridge columns were predicted by conducted collision simulations.

The second impact from the edge of cargo was found to be an crucial event causing large volume loss of concrete median barrier. Therefore, in order to improve local impact resistance of concrete median barrier during second impact, local model was developed and evaluations were conducted. Developed concrete median barrier showed the 125 kJ impact level based on conducted analysis.

Recently, overlay concrete median barrier in South Korea was newly developed. Accordingly, numerical analysis for occupant-protection performance was conducted before experimental test. In this study, dynamic analysis of vehicle-overlay concrete median barrier collision was conducted to confirm safety of driver. Furthermore, the analysis results of vehicle behavior was compared to experimental test.

This paper has a seepage measuring device installed on the water retaining wall at the bottom of the dam, but it has no seepage count and periodically uses underground water handling method to measure the level of seepage. Accordingly, observation of seepage quantities generated by the dam body is used as an important data to assess the safety of the dam body, so it is considered to improve the seepage quantity measuring device.

Soundless Chemical Demolition Agent (SCDA) has been spotlighted for demolition of concrete structure or rock near or in urban areas and historical places since it does not produce dust or rock fragmentations compared to explosive and gas pressure blasting methods. However, there is no guideline or design code for the demolition of existing structures using SCDA. In this study, numerical analysis using ABAQUS is conducted in order to find a minimum required pressure for the initiation of crack in concrete body with SCDA and obtained results in this study could be a basic data for design of hole spacing for the demolition of the structures using SCDAs.

In this study, collision analysis of overlay concrete median barrier under truck load was conducted depending on location of rebar and shear key. Obtained results indicates that the impact resistances of overlay concrete median barrier was improved as the rebar and shear keys are more closed to the top surface of the CMB.

Concrete structures built by 3D printing technology is formed as the several concrete layers. Thus, 3D printing technology for concrete structure could have less strength than the design. In this study, fracture energy (fracture toughness) tests for layered concrete in various condition was performed. depending on required time for stacking new layer. Based on the results of performed tests, it was found that fracture energy was decreased due to increased non-bonded time

Recently, the velocity of vehicle in highway has been increased due to improved driving environment. Unfortunately, the impact resistance of present concrete median barrier is not enough for increased impact severity due to increased velocity, furthermore, these increased velocity occurs another secondary accidents due to the concrete fragmentation. Therefore, in this study, the evaluation of impact resistance for developed concrete median barrier was performed with shock absorber.

Concrete structures built by 3D printing technology is formed as the several concrete layers. Thus, 3D printing technology for concrete structure could have less strength than the design. In this study, fracture energy (fracture toughness) tests for layered concrete in various condition was performed. depending on required time for stacking new layer. Based on the results of performed tests, it was found that fracture energy was decreased due to increased non-bonded time.

Objective of this study was to investigate the difference of cadmium (Cd) levels in rice grains from non-polluted fields and to define the gene associated with Cd uptake for producing safety food. Cd was analyzed by Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The average concentration of Cd in rice grains was 0.943 μg/kg and Cd levels ranged from 0.050 to 5.699 μg/kg. Genome-Wide Association study (GWAS) based on phenotype data for Cd levels was performed. However, results of GWAS were affected by subpopulation structure and caused false positive. Therefore, GWAS for rice ecotypes (temperate Japonica, tropical Japonica, Indica, Aus, Aromatic, and Admixture) was performed to minimize false positive. GWAS results showed that Os01g0611300, Os01g0611900, Os01g0611950, Os01g0612000, Os01g0612200, Os11g0444400, Os11g0444700, Os11g0444800, and Os11g0444900 genes have significant correlation with Cd levels in rice grains. The sequences of these genes were compared to sequence positions of each other gene (haplotype analysis). According to the results of haplotype analysis, Cd levels of non-synonymous group were higher than other groups and sequence of non-synonymous group was similar to that of Indica. These results were corresponding to the previous research result that Cd levels of Indica were higher than Japonica. Therefore, candidate genes detected through GWAS need to be examined by knock-out or cross breeding.

Dowel rebar is key parameter to control the lateral displacement in the sliding slab track. The lateral support block of the sliding slab track is supported by the dowel rebar. In this study, selected parameter (rebar diameter) was expected to affect the performance and behavior of the dowel rebar in the sliding slab track. Furthermore, evaluation of the shear behavior of dowel rebar compared to the results of the Soroushian et al. (1986) and CEB-FIP (2010).