Many fatal and non-fatal injuries occurred as a result of unexpected falls from horse scaffolds during structural or finishing works such as painting, plastering, or plumbing. Therefore, this study is to improve safety standards for horse scaffolds used mostly in the interior finishing works. But hazard elements for the horse scaffolds has not been specifically identified. This study has analyzed the accidents of horse scaffolds to prevent construction accidents and the characteristics of a serious accidents related the horse scaffolds. It was suggested a safety management plan and a group of accidents characteristics. The results of this study are expected to be utilized as basic data for prviding a reference related to the horse scaffolds and to be unified the regulations associated with the horse scaffolds.

This study investigated the effects of types of post-reading instructional scaffolds on university-level English as a foreign language (EFL) learners’ WebQuest writing performance. One hundred twenty students, randomly selected from 8 EFL classes at a Korean university, were randomly assigned to one of three treatment conditions: (a) online Instructional Conversation (IC), (b) online recitation, or (c) no post-reading instructional scaffold (i.e., control). After reading WebQuest texts, the online IC and online recitation groups received their treatments, using an Internet-based synchronous textual communication tool as a medium for communication. The control group, on the other hand, did not receive any post-reading instructional scaffold and continued to read the WebQuest texts for the same amount of time that the IC and recitation groups received their treatments. Results showed that the online IC group outperformed one or both of the other two groups in overall WebQuest writing performance and in the specific areas of overall writing quality and content. Implications are discussed in both theoretical and practical terms.

Using a polyurethane foam replica method, porous hydroxyapatite scaffolds (PHS) were fabricated using conventional and microwave sintering techniques. The microstructure and material properties of the PHS, such as pore size, grain size, relative density and compressive strength, were investigated at different sintering temperatures and holding times to determine the optimal sintering conditions. There were interconnected pores whose sizes ranged between about 300 μm and 700 μm. At a conventional sintering temperature of 1100˚C, the scaffold had a porous microstructure, which became denser and saw the occurrence of grain growth when the temperature was increased up to 1300˚C. In the case of microwave sintering, even at low sintering temperature and short holding time the microstructure was much denser and had smaller grains. As the holding time of the microwave sintering was increased, higher densification was observed and also the relative density and compressive strength increased. The compressive strength values of PHS were 2.3MPa and 1.8MPa when conventional and microwave sintering was applied at 1300˚C, respectively.

Porous poly(e-caprolactone) (PCL) scaffolds were fabricated by salt leaching method. The PCL scaffolds were treated with aqueous NaOH for 0h, 2h, 4h, 8h, and 12h at 40˚C. The NaOH-treated PCL scaffolds were dipped in CaCl2 and K2HPO4·3H2O solution alternately three times to induce apatite nuclei onto the surface of the scaffolds. The NaOH-treated PCL scaffolds were immersed into SBF solution for 1day to grow the apatite. The apatite formation were investigated as a fuction of NaOH treatment time. The hydrophilicty and surface area of the PCL scaffolds were increased with NaOH-treatment time. The NaOH-treated PCL scaffolds were successfully formed a dense and uniform bone-like apatite layer after immersion for 1 day in SBF solution.

We evaluated the influence of internal macro- porous structure on tissue-engineered bone regeneration by cOll1paring the effi cien cy of scaffold-cell construct forll1ation and its bone induction activity. T매o types of macro-porous CMP cera rnic blocks having 400 um average pore s ize in an interconnected trabecular framework and interconnected globular structu1'e with small fenestrations were prepa1'ed, adopting sponge method and foaming method. respectively. They ware evaluated by cytotoxicity. cell ular attachment. and t heir differenti ation in vitro and the histocompatibility, osteoconductivity, and ectopic osteoinductive potenetial in vivo, respecti vely. Both scaffolds having either interconnected trabecu lar pOI‘es formed by sponge ll1ethod 0 1' fully interconnected globu lar pores formed by foam-based technology were no cyt otoxic and induced neither an immune nor an infl ammatory response regardless 0 1' geometry and manufacturing methods. The fu lly interconnected globul 81 porous scaffold showed more favora ble compression strength compared to the interconnected trabecualr porous scaffold (8.7 :tO. 5 MPa va 5. 5:t0. 5 MPa) . The increased surface in fully interconnected globular po1'ous scaffold facilitated osteogenic repall‘ by favored cellular attachment and osteogenic differentiation with good osteoconductivity. These results suggest that the fully interconnected globular porous structure be more sui table for both bone s ubstit ute and scaffold for t issue-engineered bone regeneration‘

Particulate leaching method for the preparation of porous PLLA scaffolds was carried out and especially, the effect of PLLA/CHCl3 solution concentration on the salt leaching rate and the pore structure of PLLA scaffolds were considered. It was found that maintaining lower PLLA/CHCl3 concentration and higher CHCl3 evaporation temperature in the preparation of PLLA/NaCl mixtures resulted in the enhancement of salt leaching rat e and higher porosity. This is understood that those conditions could minimize the formation of dense PLLA layer on the surface of PLLA/NaCl mixture as well as introducing better porosity on the surface. Higher salt leaching temperature accelerated the salt leaching rate but it seems that there is no influence on the porosity of PLLA scaffolds.

곡선 승강장에 직선형태의 전동차량을 운행해야 하는 물리적 구조의 한계로 인하여 승강장 연단과 전동차 사이에 발이 빠져 발생하는 승강장 연단 실족 사상 사고는 어린이와 휠체어를 이용하는 장애인을 비롯한 교통약자의 도시철도 이용에 큰 위험 요소로 작용하고 있다.최근 도시철도 승강장과 전동차 사이의 간격을 방지하는 안전발판에 대한 관심의 증가로 관련 특허 및 연구가 활발히 이루어지고 있으며 서울시에서는 3호선 경찰병원역의 시범설치를 비롯하여 곡선 승강장에 대한 전면적인 설치를 계획하고 있다.따라서 본 연구는 도시철도 승강장 연단 간격 발생 원인과 건축분야의 승강장 설계 기준인 도시철도 건설 규칙 및 도시철도 정거장 및 환승·편의 시설 보완 설계 지침 대해 고찰 한다. 또한 연단 실족 사상사고 분석을 통해 승강장 안전발판의 필요성과 승강장 설치형 안전발판에 대해 연구하고 대안을 제시하고자 한다.본 연구에서는 지하철 운행 중 발생하는 사상 사고의 경우 많은 경제적 손실과 더불어 인명의 피해로 연결되는 경우가 많으므로 승강장 안전사고를 저감하고 동종의 사고에 대한 재발 방지를 위한 개선 방안으로 곡선 승강장에서의 승강장 연단 실족 사상사고 예방을 위한 안전발판에 대한 기준의 제시에 의미가 있다고 생각되며 향후 안전발판에 대한 연구가 지속된다면 도시 교통의 중추적인 역할을 하고 있는 도시철도에서의 안전성 확보에 중요한 자료가 될 것이다.